Hutch's is a welcoming little retro diner that exists simultaneously on every Earth in every reality. Whether it's a world like ours, a world ruled by a race of intelligent dinosaur people, or a bleak dead world without an atmosphere or oceans there will be a Hutch's All-Night Hamburgers somewhere and inter-dimensional travelers will have a safe place to rest for awhile.
Hutch himself, the owner of the diner, is very similar in nature and exists in all realities at once. Just like the diner his appearance varies depending on who's observing him but he's generally a deceptively normal-looking man. What he truly is is a mystery but whatever being could create a place like the diner and simultaneously run an infinite number of them at once must have great power. It's lucky that Hutch chooses to use his power to feed and chat up fascinating travelers from different realities rather than acting as most gods do.
If someone causes trouble in the diner Hutch won't harm them, but whatever is waiting on the random Earth he kicks them out onto might. It's best to just enjoy his hospitality and meet some interesting characters. Hutch will even let you out at the reality you wish when you leave.