naughty-gift scavenger

A low-income person who trundels a wheelbarrow all around town on Christmas morning and collects the lumps of coal that Santa left in the stockings of all the bratty youngsters, so that he can take it back home and burn it in his stove for heat.

As we all know, Santa is extremely careful about determining who's actually been naughty or nice ("He's makin' a list, and checkin' it twice"), and so quite a significant percentage of the children in any given area will probably receive high-grade anthracite as their Christmas present. A naughty-gift scavenger, therefore, should have little trouble filling up his 'barrow come Christmas Day, since most parents wouldn't want "that dirty black stuff" in their houses, anyway, and thus they would probably be all too happy to be rid of it; about the only families who would likely tell him no would be fellow-indigent folks who themselves would want to use said sooty lumps in their own furnaces.