My dad was dumpster diving long before recycling became the thing to do. He would bring home cans, cardboard, newspaper, food. By the end of the week we had enough to buy breakfast after we dropped it off at the salvage yard.
So I have been dumpster diving for about 37 yrs. Had alot of meals from those grocery store dumpsters and alot of wine made from the fruit they would throw out.
It's amazing what people throw out. Once we got a box that had 4 old railroad lanterns in it.