In St. louis everybody dumpster dives and if it's in an alley next to or in a dumpster we consider it fair game - for 2 reasons, 1 the city pays for the dumpsters so it's not *your* trash can, and 2 lawyers have proven in court that if you intend to throw something away and exhibit this intent say by placing it in, on or near a dumpster etc. it's not yours anymore.