It's happened to all of us. You get home from the store, tear open that package of chips, and find it's already half empty. Whether it's complicated billing, poor or misleading labeling, or mountains of fees, there's a lot of ways you can end up getting less than you thought you were buying, and that's always a disappointment. Here are some of the most common instances where you might not be buying exactly what you expect. Prepackaged Foods You don't have to look very hard on grocery store shelves to realize that some food packaging doesn't do a good job of accurately explaining how much you're going to get. Remember the bag of chips we were just talking about? It's hardly the only package on store shelves that's only partially full. In the industry, this is called slack-fill, and it's an easy way for companies to give you less product for the same price tag. Though nonfunctional slack-fill is banned by the FDA, slack-fill itself is still not uncommon, as companies come up with practical reasons that empty space is necessary — with chips, for example, the extra air in the package is meant to keep them from getting crushed. The deceptive volume is just an "added benefit." Cosmetics The problem of slack-fill isn't limited to food. It's common in cosmetics and beauty products, too. Ever noticed a tiny bottle of lotion packaged in a big box? Or bottles with false bottoms to make them seem bigger than they are? It's more slack-fill, though cosmetics companies will usually argue that the bigger packaging is needed for space on which to print product information. SEE ALSO: There's a 50% Chance You're Overpaying for Almost Everything Nevertheless, companies have actually been prosecuted for slack-fill in cosmetics. Procter & Gamble settled a suit in 2015 and CVS did the same in 2014. But that doesn't mean the end of slack-fill in the cosmetics department, so continue to be wary of oversized boxes. Video Games When you buy a brand new video game, you expect the disc (or download) to contain the whole game, right? Unfortunately, this is increasingly not the case as downloadable content (DLC) becomes more common. These gaming add-ons usually cost something extra in order to get more story, more areas to play in, or more gear for your character. You'll even find DLC available on the day the game launches — and that has to make you wonder why it wasn't just in the game box. The result? You're shelling out $5 or $10 at a time to buy a game that would have once just been one piece. Shrinking Food Products Sometimes it's not that the packaging is larger: it's that the product is smaller. Candy bars are a big — albeit shrinking — item here, as manufacturers have tried to keep the calorie count on the label reasonable. That, of course, usually means you're getting less candy for the same price. The packaging may be slightly smaller but looks the same, the lower calorie count makes it an extra appealing afternoon snack, and you probably didn't notice that it's an ounce less chocolate. You can find similarly shrinking products in the condiments aisle, too, where redesigned packages with fancier shapes may hide the fact that the bottle is actually smaller. Airfare So, you've been comparison shopping for airfare and finally found the low price that fits your budget perfectly. It seems ideal until you get to the checkout and realize you have to pay more, anywhere from $1 to $200, just to avoid getting a middle seat at the back of the plane. SEE ALSO: 5 Ways to Save on Your Next Flight Then you get to the airport and find out it's $25 to check a bag, plus an extra $50 to $300 if your bag is over the airline's size and weight restrictions. And when you're on the plane, you may find yourself paying another $5 for a bottle of water and peanuts. Suddenly that fare doesn't seem like such a bargain. Fees are the name of the game as airlines try to stay afloat, which means you need to take care if you want to avoid the bait and switch of low up-front prices but a big bill before your trip is over. Credit Cards and Banking Services You may be surprised to find out just how much low-cost banking services and low-interest credit cards will actually cost you. Whether you're shopping for a new credit card or a car loan, you're probably on the hunt for the lowest interest rate. But you won't get the rate banks are advertising without great credit. If your credit rating is subpar, you'll be handed higher interest rates no matter what the advertising said. Similarly, if you're in the market for a new bank account, low-cost (or even "free") accounts are often a terrible buy. The trick? They're usually piled with fees, so that while the account itself is free you're still paying for it, and maybe even paying more than you would for an account with a monthly service fee. Cell Phone Plans Even though cellular carriers continue to jockey for which one of them has the simplest plans and the best values, cell phone plans remain complicated. How much data do you use? Would a family data plan be a better buy? Do you need rollover data? Even once you've picked a plan, not all carriers offer an easy way to track your data usage (a third-party app is still the best way). That can leave you hit with overage fees even if you think you picked the perfect plan. Trying to track down where you went overboard with data usually means digging through a bill that's dozens of pages long. And while tech-savvy shoppers may be okay here, it's easy for the rest of us to get lost in the fine print. Internet Service While home internet service plans aren't usually as complicated as cellular service plans, their advertising can be misleading. Most plans are based on the amount of bandwidth you want, but few consumers know how much bandwidth they actually need. Even if they do have a good idea — perhaps basing it off Netflix's bandwidth recommendations or something similar — those promised bandwidth numbers may not be what you get. Why? All carriers note (in fine print) that speeds are "up to" a certain amount. At busy times of the day, you may get less speed as everyone else in the neighborhood tries to stream their favorite shows at once. This can get even more difficult for plans with bandwidth caps, as there's no easy way for the average consumer to keep track of their home bandwidth use. And ISPs provide even fewer tools for home users than cellular data providers offer mobile users. Streaming Services Speaking of streaming, Hulu and Netflix subscribers know well the frustration of not getting what they think they paid for. When you log in to watch your favorite show, you may find the episode isn't available yet. Or has already expired. Or simply isn't there at all. SEE ALSO: Hulu Will Soon Offer Live TV for Less Than $40 With Hulu for example, you probably bought into Hulu's description of its own service: "Watch premium original series, full seasons of hit shows, current episodes, movies and more." But the shows available are limited, how long they're available and when they show up online varies. Plus, each service has its own unique selection of networks that are — and aren't — included. What Can I Do About This? Fortunately, a smart consumer can avoid all of these problems by taking the time to read through the fine print on any product or service before committing to buy. When you're at the grocery store, pay attention to the weight or volume of a packaged product before you decide to toss it in your cart. Some stores will make price-comparisons even easier by providing a price per ounce on the shelf label. For services, it's important to read through all the details of the contract you're signing up for. Pay close attention to fees or charges you don't expect. Yes, it's more work up front, but it will save you from the disappointing feeling that you didn't get exactly what you paid for. Readers, can you think of other examples of products that commonly come up short? Let us know in the comments below! Related DealNews Blog Posts: There's a 50% Chance You're Overpaying for Almost Everything These 13 Foods Aren't What You Think They Are What is Drop Shipping and What Does It Mean for You?