Yeah i dont like the ability to be able to buy 1 item from a stack. I can't open a pack of Oreo cookies in Wal-Mart and buy just one Oreo, I have to buy the pack.
I post discounts for buying in bulk. I'd hate it if someone could just buy 1 from that stack.
Thats kind of a bad analogy. A grocery store doesnt sell you 30 oreos. They sell you 1 bag of oreos. If on the market boart im seling 30 sheep leather, thats not 1 pack of leather, its 30 individual leathers.
Also, it does suck that you cant buy as many as you need. Sometimes just 1 isnt on he AH and thats all you need. People who need only 1 should be able to buy 1 while people who need a stack can buy a stack. This doesnt stop you from giving out a discount.
The bag of oreos may have the set amount of oreos in it though. You can't just pull one out to buy it.
When you put up the leather, you're deciding what size group of leather you're selling. You can set it to whatever amount you want, and this puts pressure on you with pricing so that you don't just sell a hundred individual sales of something since you have limited sales slots, so you instead have to sell in stacks of some sort, and decide for yourself a sensible amount that will actually sell instead of just plopping 150 leather on the market board and hoping someone needing over a hundred leather will buy it.
This helps to keep people from putting too many of these things on the market board as well. Which is a good thing, since it means you don't end up with something like one crafter deciding they're going to sell EVERYTHING, that they'll be the only game in town and just put up everything everyone needs and essentially push out every other crafter in the game.
WoW lets you put up unlimited auctions, and that's pretty much what happens there (or people attempt to). Which helps buyers a lot, but screws over all sellers since prices then drop like a rock as everyone is then undercutting like mad.
What you're suggesting would make crafting worthless.