How could Melvin trust the cooks' at a diner?

I mean he's incapable of using the same soap for more than a few seconds at a time, but he's going to eat food every day that's been prepared by staff who despise him? I would be surprised if they didn't mess with his food every single day.

If he was as paranoid as he's supposed to be, he would only eat meals that he himself had carefully selected and prepared, which it seems is what he did for his other meals by all the food in his fridge, which makes it even more odd since breakfast is the easiest meal to cook. He can't make his own eggs, sausage and bacon?