Right now my cats (16,11 and 10yrs) are strictly indoor cats. When we move out of the city I intend to let them outside. I leave dry food down for the cats all the time in one of those feeders that drops it down into the tray as they use it. They help themselves.
Our dog is a different story! She hates everything I put down for her and I've tried most of them. Right now she's getting half a package of Pedigree moist food (which one of my cats eats most of) and a handful of dry food which she won't eat til she's sure nothing else will come her way. She loves people food, spaghetti sauce, chicken, any vegetable, even pineapple and bananas, if we're eating it - she wants some and if it's not high calorie (she's a 5 lb dog) she'll occasionally get some from the guy with the "S" (for sucker) on his forehead who eats with me.