Yes, that's often the case,But I once knew someone who managed a charity shop, and she assured me that, in order to comply with The Sale Of Goods Act, it was standard practice for all donated articles to be checked over on receipt to ensure these were deemed "Fit For The Purpose" of being put on display and/or sold. This was particularly true when it came to sifting through merchandise to eliminate electrical appliances which, by law, they were not permitted to sell.
Not so, with car boot sales, I understand!