I've never invested real money in my characters, in fact I got a few hundred euro out of the game. You just need to understand and be able to trade on the auction house which is something I absolutely love doing but the majority of the players hate this.
Also, a lot of people fail to realize that D2's Hell is not D3's Inferno, it's D3's ... have you figured this out yet .. yes it's D3's Hell, which you can without a doubt clear without ever opening the AH and which you can get tons of upgrades for your character if you haven't relied on the AH. Inferno was demanded by players as endgame for the pros and the really dedicated players but now every casual player thinks he's entitled to being able to clear it, even though he sucks at the game and/or hasn't spent nearly enough time farming for items. BTW, two people cleared Inferno on Hardcore a month after release, and the hardcore auction house didn't have a bunch of easy-inferno gear, so the argument that you can't do it without the AH on softcore is just plain wrong.
Another thing people fail to realize is that if the game dropped awesome, near-perfect items more often and there are still no ladder resets, everyone will have them and consequently there will be nothing special about having those items which will make searching for loot more meaningless, not to mention the whole market collapsing.
I'm not saying Blizzard didn't mess up, but one of their biggest mistakes seem to be that they listened to some of the ideas of their fans, who want something and then bitch about it when they get it (ex. very hard 4th difficulty). Blizzard fans sometime remind me of clients who don't know what they are asking you to do to the mix and then blaming you when they don't like it.