While looking through the interface thread, a thought occurred to me that might have already been addressed. Didn't the early version of the game allowed you to only buy one item at a time? That is, if you wanted to purchase twenty flasks of water, you would have to click buy twenty times.
I remember one of those online EverQuest comics (Woody?) making fun of it.
If this has already been addressed, then please disregard this post.
Stack of Honey Mead 1
Stack of Honey Mead 3
The latter comic was from April 20, 2001; so perhaps that was when multiple buying went into play.