Perhaps You right, but remember that those items could have much higher price.
On alpha server probably in that way there wont be any of epic or legendary items, because there are not so many active players.
Dont get me wrong. I am playing on alpha and beta and I can say these two servers are very different. On alpha players rely on NPC shops to get new equipment, whilst on beta almost everybody buys their stuff from auction house. I bet programmers are trying to make some sort of compromise between these two (NPC traders and auction house sale). Indeed for alpha sadly you are right. We will never see legendary or epic items. Crafters are few (as players by the way) and if they manage to craft something legendary/epic, they will use it not sell it.
P.S. By the way I think I found something like a bug. When a player puts something for sale in auction house and the price is in diamonds he/she avoids paying fees to the house. I'll explain: for example if the selling price is 1 diamond, the fee is 15% max, the house cant get 15% of 1 diamond, so the selling is without any fee. I think this should be fixed somehow.