Sure.. They'll appraise it for the owner, then the buyer, act as a buyers agent, hold whatever they negotiate the appraised vaules at in escrow, charge for each of these services to both parties, then make 10% off the sale anyway. And ya gotta wonder when they appraise low, who's actually the buyer? Always amazed me too.
Howver, that being said, they do have one of the best venues of selling a domain out there. Just gotta look out for yourself.