Spending money in the fast food industry can be harmful because it supports illegal usage of drugs in food and genetically modified organisms. Say you purchase a burger from McDonald's; the beef used could have been real at the time, but when more and more people begin purchasing burgers, and they don't have enough beef to supply, they will create more. The company may begin using illegal growth hormones to make a cow larger and bulkier, or genetically modifying cows to make them larger. Not only does purchasing items in the fast food industry support illegal activities, but the usage of hormones and drugs could harm you as well. You would never know what happened in the creation of that burger, but you do know that it tastes good.