I'd hate to be in a position where I had to send a child unaccompanied. I know it can't be helped in some situations.
I also know that if the airline screwed it up I'd be like to hang a badge of shame on the guilty employee, and ask that they stand in the terminal wearing the badge, and loudly announce for an hour, to everyone passing by, that they had failed and were incompetent. I saw that once on a 60 Minutes piece about a Japanese executive training course. It seemed harsh, but if it involved my kid I'd get over the harshness. I would want this in lieu of a bunch of legal crap. Object lessons seem to work better.