I'm a designer, honestly, a logo takes a few hours. If they want 15 variations, extensive input, full service, they're going to have to pay someone local by the hour. Or they can try betting on 99 designs. It helped me hone my skills early on, and the criticism was just as loud back then. I think the complaints have more to do with designers wanting to 'pull the ladder up behind themselves'.

EDIT: Forgot to add, 99 Designs does not supply the most important ingredient: judgement. If a client with no design sense uses 99 Designs they will pick a crappy logo, while a professional designer may have been able to steer them in the right direction. Their loss.