I don't know...there's a market for everything. If I'm going to hate on the guy that charges $15 for design, then I have to hate on his customers to, and IMO, he's doing us a favor by getting the tire kickers and cheapskates out of the equation. I think it's lame, but average design is becoming a commodity.
You know, for a fresh design for my personal blog, or another take on something, $15 is great.
Would I use it for client work? Uh, no.
What's the worst that could happen? He gets too busy? He flames out after a couple weeks? Either way he got some experience and learned some stuff and built a portfolio and got paid to do it.
Way more upside than downside.