On Mon, 26 Dec 2011 16:43:44 +0000, Adrian Simpson
wrote:

Round here, they seem to be permanent fixtures. Not looked inside one,
but judging by last year, they must get replenished periodically.

Last time I looked inside one it was full of crap.
Otoh, they make useful emergency shelters when you're stuck by the
side of the road in the Highlands.