Que, don't take jaysen's advice! It's a trick!
Yeah, that is one FAT turtle. I'm surprised a wildlife center would let it get that fat. Obesity in animals is way more unhealthy than in people. Well... People are animals too...
Snapping turtles can actually become very tame. I used to belong to a turtle forum when my turtle was alive and this girl's snapper had a dog bed and she would come into her room to find that he climbed out of his tank and climbed up into her bed and was fast asleep. She could sit next to him and everything. I don't know about petting.
The only fair way to keep them as a pet is to make sure that you have a HUGGGEEEEE aquarium because they need a lot of room to swim or a pond. Obviously. I want to get one one of these days... When I put in a pond of course. Or not b/c I wouldn't be able to have any other turtles in the pond.