Really, I'm curious. Who's buying this stuff? I've seen goldsellers advertising gold in amounts of up to 11,000 -- for over $1600. Perhaps you're doing a double-take at that number, but it's not a typo -- I do mean sixteen hundred dollars. Now, I paid $50 for the game itself, another $50 for the expansion, $15 a month to play, and the occasional $25 to move characters around, which means I've spent over $500 on this game in the two years I've played it. That already seems like a huge amount of money to me -- but if gold sellers are out advertising $1600 worth of gold, that must mean that at least a few people are interested in spending that much.
All I can think of are the cries of agony that surely follow when the buyer is inevitably banned from the game. Blizzard does keep track of gold transfers, and I imagine that transfers in such high amounts set off red flags in their system. So what happens when you've just spent $1600 on virtual property that Blizzard has politely reminded you belongs to them? (Yes, Blizzard does hold on to the idea that all in game items are their property, and thus cannot be bought or traded for real money.) I can think of less risky ways to invest!