Why do buffets request that you use a different plate each time?

Question

Just wondering, since I wouldn't mind using the same plate over.

Answer 1

because who wants to eat food that is near people's dirty plates.

Answer 2

Sanitary purposes

Answer 3

It is a health department requirement.

Answer 4

it's more sanitary.

Answer 5

It is the law by the local health department, to avoid any possible contamination.

Answer 6

so none of your left over food or spit or anything else gets in the food.