The original purpose of buffer is to reduce waiting staff which people can serve themselves. Unfortunately, this term is equal to "All you can eat with a fixed price" nowadays.
I am not the type of person who wants to eat buffet until you throw up and I usually very picky about the food. The problem I have is that I try a little bit here and there and it adds up pretty quickly and you overeat without even noticing when I am eating buffet.
It takes me 50 minutes to burn 500 Calories on a threadmill machine. I probably abrobed additional 1000 calrories than I should. I am a sorry ass now.