I'd dress up in an official (police like) uniform, and stand outside the door with a little scanner, maybe like the stuff you check purchases with at stores (you get the idea) and when fatter people start to walk towards the door, I'd "scan" them and announce that their calorie intake was to high and if they ate too much here there was a strong chance of them dying, and ask them if they could sign this paper that I got their house/car/sound system when they died of eating the burger inside.