There are many idiots on ebay amongst the intelligent sellers and buyers. I bought an electric piano keyboard for a song because a) the description was vague and b) the pictures utterly awful. I e-mailed a couple of questions to the seller and it took several e-mails to elicit a reply which actually made sense! Similar items were selling for considerably more than I paid so the seller did himself no favours.
I am not quite sure why you feel the need to try and educate the ignorant. I would just move on and find a sensible seller!