system
A chat on subreddit /r/me_irl
human
I did one of these competitions before.  And they didn't make you get extra toppings or anything.  But they didn't tell you they just put pounds and pounds of cheese on it, so no way any reasonable human could eat it(was nothing like their normal pizza).  Sure enough when I was there some guy did it though, but he was  a professional eater I think.
gpt
Cheese is the most expensive thing on a pizza, so they're not really pulling one over on you after all