Selling accounts s illegal. ILLEGAL.
Actually, the legality of something depends on the jurisdiction under which it happens. Claiming that something is illegal without referring to a jurisdiction does not work on the internet.
Selling and buying forum accounts isn't explicitly regulated in any jurisdiction I know of (which aren't that many, I have to admit) so it's probably not illegal in most places where users of this forum reside.
Within this forum, trading accounts is allowed because basically even if you forbid it, you can't effectively prevent it, so why bother?
By doing this you might enable scammers to gain more credibility and scam other people. Is this really worth fcking $10.
But of course you're right that selling accounts may enable folks to scam others. However, there are so many ways to scam, so any attempts at fixing this loophole won't really help much. Instead people should learn to check others' credibility while being aware that accounts can be bought.
To me, bitcoin and this forum are a very interesting experiment not just in economics but also in human behaviour under the preceived protection of anonymity.
Onkel Paul