However, since there are people that are insanely wealthy thanks to Luna (or cheating), and many of them are complete a**holes who only care about money, it's most likely that if EA put something like that into the game those people would simply buy everything possible on the shards cheaper than their own prices and the end result would be the same.. you'd have to go to specific people to get anything, especially since there are plenty of scripters who could monitor the list 24 hours a day (could set up a complex script to buy any of a specific item thats cheaper than your price the moment it showed up on the list, im sure). And they wouldn't even have to sell the items, either! Having unlimited access to buy them means they can drain the market dry of those resources and charg whatever they damn well please for their own goods... you really want to see iron ingots at 1k gp per? A global vendor search would literally allow one or two people on every shard to monopolize the entirety of the game's economy. You can't even say i'm just being paranoid, i'm sure you've all seen what I mean in some form or another and know damn well there are people on every shard who would do it the moment it was put in. The only reason they don't right now even with the searchers there are is that there ARE all those alternative vendors on the shards outside of those cities.. currently its entirely possible to offer things much cheaper without worry.
What they need to do is work to shut down the search sites actively.. leaving them open only leads to complaining like this topic. It's a wonderful idea in theory, but in practice it would most likely kill the game, which i'm sure is why the devs have never done anything like it.
Actually, it would have an opposite effect. Vendors outside the two search sites range don't do very well these days. The reason is, as people have said, its just much easier for someone to type in what they want and find it than to run around several facets trying to find it.
As for someone buying up all the supplies, so what? If I am a vendor selling 'X Item' on my vendor for 2 mil and some other vendor buys it then turns around and sells it for 10mil, I don't care. I made the 2 mil I wanted. Then, nothing will stop me from getting another 'X Item' and selling it again for 2 mil. A greedy vendor can have 200000 vendors full of overpriced items but if no one buys from them, they won't last.
It would actually benefit the community as a whole for those greedy vendors to even try to monopolize. If I searched UO's vendor database and found 'X Item' on a vendor for 2 mil then when I got there it was gone but all of a sudden it showed up on Greedy Vendor for 10mil, I would talk to the 2mil vendor and arrange a private purchase. More immersion. Then the 2 mil vendor would have made 4 mil from selling two 'X Items' while greedy vendor would be out 2 mil and have an item no one will buy from them.
As it is now, vendor play is limited mostly to those in and around Luna or Zento. The best vendor houses on my shards closed all because of these search sites. If UO cared at all about the community, they would take steps to ensure that people that have supported the game for years and provide a nice service to players would want to stick around.
The devs are going to be hard pressed to 'get rid of' the existing search sites. Instead of wasting time trying to fix something that will just pop up in a new form as soon as its fixed, they should put things in that makes those 3rd party type things not necessary.