Yeah, they do this to ensure the cheese gets melted, but also to give the patty a little extra warmth before being served, providing the illusion that it is still hot off the broiler, even though its been sitting in a pan of its own fat for the last 40 minutes (the amount of time a batch of burger patties are allowed to be kept for before being thrown out).
Is this what turned you into a veggie?
vegetarians & vegans = lesser form of human being, IMHO