Most charity shops are run by volunteers and have to put up with receiving lots of junk from the public on a daily basis. Many donors use charity shops to get rid of their junk because they can't be bothered to visit the local recycling bank.

I have volunteered in a charity shop and was amazed at the items some people would donate. I mean, sex toys and used underwear are hardly items you would want to see on the shelves in a well respected charity shop!