Citan has some an blogpost (that I'm sure Beta can find!) that talks about MMO-market theory.
Some players put prices in their shop title, and that practice throws a wrench in the overall plan. If I remember correctly, the convenience supports flipping items and people make money by just sitting in the market. If you played on the EQ-time lock servers in the past few years, something noticeable changes when they introduce the expansion with the bazaar. I believe what happened was the wealth distribution became less even.

Avoiding deep MMO market theories...
I use the snippet tool in windows after I search for an item, to temporarily save whose selling what and I remember the lowest number after running around. If 10 people are selling something, I rarely check all of them, but just find an acceptable price vs the best and I think that's the overall goal. I see Bob is selling something, I know Bob is a good guy, I might shop with him vs someone else if he has a fair price. I know if I had all the prices in front of me, I would just buy the cheapest.

Side note question, what item were you buying that made you question the system? I ask because most of the time if you dont need it now-now, a work order is usually cheaper. The game rewards long-term planning big time. Player stalls are buy-now prices where the work order board usually "can someone sell me this in a week?"