its called inflation... its a natural part of all markets. if you want to avoid it put your money into items
Actualy, its DEVALUATION: the crpg gold is worth less, not the looms more.
Also, much stupidy in this thread: items of equal shop value are NOT equal ingame. The prices are fairly random between weapon types, IE a fairly equal potency weapon from one class is not the same price as another class.
Ultimatly, the ONLY way to stabilize the market, if it was so wished, is to make upkeep an actual factor, not just a joke. Currently if you cannot use what you want whenever you want, you arent doing it right.