Every day is not good. But having these things on occasion I feel is fine.
Today, the children I nanny had Burger King (100% beef) burgers. I think we do this about twice a year... it's very much a treat. Usually they get far more healthy things such as cheese sandwiches, rice cakes, pasta salad, potato salad, fruit selection, fruit salad, veg rice, tuna rice, tuna pasta bake, that sort of thing.
We do go to the local craft baker more often than perhaps we should. Once or twice a week, but I find it cheaper to buy them something rather than make it. We do lots of baking at home, but when I do that, they don't just eat one - they eat many. Whereas from the baker they just eat one. It's hard to find the right balance, tend to get yeast based things from bakers, and make non-yeast things at home (muffins, flapjacks, scones, cheese straws, welsh cakes, etc).
Chips - we have these once or perhaps twice a week. Tends to be after swimming, or as a treat when out (such as today). At home I occasionally do sliced potatoes fried, though I prefer not to do much fried things at home.