do you hate when your food touch each other? If so why?

I have a friend who just told me that he hates when his food touches his other food. I had lady just tell me the same thing about herself a few weeks ago. My niece is like this too. There seems to be quite a few people in the world like this. I'm just curious, if you are, why? Everything is going in the same place anyway. And what about things that already have food merged together like tacos, pizza, hamburger, casseroles, sandwiches, etc.?