USA Today looked into how fast-food restaurants gets customers to spend more money.
According to research, French fries and soft drinks are pretty much pure profit for restaurants.
They also make money by offering additions such as guacamole.
They also get people to pay more by offering items for a limited time only.
For example, Starbucks is currently offering zombie frappuccinos.
And once you are there for a limited-time offer, they count on being able to sell you something you did not come for.
Also, restaurants make more money if you order online instead of in person.
Another that fast-food restaurants want you to buy that will make them a lot of money include alcohol.