Litter boxes I usually don't have too much of an issue with - but I also try to make sure there's at least one per floor, usually in a bathroom or laundry room. I also try to follow the real world guide of one more litter box than I have cats. They'll occasionally get red/uncomfortable, but will eventually go. (I have had to occasionally reset the litterbox when it wasn't cleaning correctly, though.)
Food, on the other hand, there's some sort of bug or something, because I'm regularly calling the cats over to eat at one of the food bowls. Same with dogs. Though food I do keep just in the kitchen.