system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How do buffets stay in business?

It seems that people who eat a $5 buffet usually consume more than $5 of food. Why don't the buffets lose money?
gpt
In the food service industry, most of the costs aren't food costs, but rather operational ones. Electricity, rent, and the big one: payroll.

Buffets, being self service, are able to cut down on the cost of employees, as they don't have to hire servers. They can cut down (somewhat) on cooks because they're not cooking to order. In exchange is a minor increase in food costs.

Further, most buffets will buy lower quality food (the ones that offer higher quality food tend to be more expensive than $5), which makes a difference, but not as much of one as most people think. 

Really, though, the big one is payroll. Not paying waiters makes a huge difference.