I don't have a problem with people asking any price for anything on eBay, you see it all the time with antiques, for example - as long as the item is as described and the pics un-photoshopped! I guess the word 'mug' applies to people paying over the top for these items, without doing any due diligence, and not returning them if they are not happy. However, when it comes to experienced coin sellers, while it doesn't breach any rules, trying to take advantage of human nature lusting after a bargain, without offering a grade or current price guide, is not going to win many friends or loyal customers.