Too bloody true, I do one every now'n'again to have a clear out and it never ceases to amaze me, and not in a good way. The last one I did (last Sunday) I sold a working Arc Welder with cables for a tenner and most were still turning their noses up. Sold a £200 trolly for £30, had many an offer of a tenner.
About seven years ago I sold a BSA Goldstar at one for £90 (couldn't get along with it) again still had the offers of twenty quid here n there.
*shakes head
Ye do get the odd useful bargain though is ye look around like the odd rifle (though rarer to see down here in London, all behind closed doors n all that). Picked up a very nice very early Kukri for a couple o'quid.