Where can I convert that stuff to dollars? Yes, they have "value", but they aren't currency. Often there's a "market" you can find to convert real world currency in to game junk. But there are no symmetrical markets for buying dollars with game current. That's a vitally important distinction, and part of the definition of a currency.
Bitcoin is a currency. It was designed that way, there is no attempt to hide that fact, and everyone involved knows what it is. Pretending that a currency exchange won't be regulated like other exchanges is just fantasy.
In the case of Diablo3 you can buy in game gold for money off the real money auction house.
Going the other way you can sell gold for money on the real money auction house and in return can receive the money into a PayPal account.
There is a transaction fee of 15% of the total sale price for converting to real money. This is on top of the transaction fee for selling the item on the real money auction house which is either $1 (items) or 15% (consumables including gold).
So sending money from one person to another via diablo3 gold would cost 30% or possibly less if you buy items with the gold you buy and sell them on the real money auction house, though that's probably slower and more time consuming.
Alternatively you can transfer the money to a Blizzard account, which can be used to buy items on Blizzard's own store. This avoids the 15% fee for the transfer of real money (but not the listing fee). However, laundering money with Blizzard merchandise is probably a risky business. That said, if you bought enough of a game right around it's release that was popular it might be worthwhile.
PayPal itself is a registered MSB. So that may avoid the issue for Blizzard in the case of the route of converting to real money via PayPal. However, I'm not clear if the regulation applies in the case of buying goods and services from a Blizzard account.
I'd say the fact that you can trade gold in game between players is itself another problem for Blizzard.
Bitcoin is a currency. It was designed that way, there is no attempt to hide that fact, and everyone involved knows what it is. Pretending that a currency exchange won't be regulated like other exchanges is just fantasy.