Why should they accept bitcoins? Aside from you just wanting them to, that is. Who is unable to pay them in a currency they accept but who would pay them in pretend internet coins? Do even five of those people exist?
You're right in your first post, this is a complete waste of your time. But that's not an uncommon theme with bitcoiners.
In that case, why would anyone in the world accept bitcoins as a payment method

?
Time-cards are a hassle. If you don't have a credit card, it's pretty much your only option.
Stability means nothing when you're basing the price off of gametime cost/btc. Value of btc goes does -> price (in terms of BTC) goes up.
Did you seriously ask about withdrawal limits, MeSarah? We're talking about Blizzard, not some third-rate nobody. I'm sure if blizzard decided to accept bitcoins, any exchange that was dealing with them would not be stupid enough to tell them they can only cash out $1000 per day because blizzard would be bringing them a massive amount of revenue.
People used to laugh at the thought of human flight, look how that turned out.
EDIT: Even if they do not decide to go through with it, at least bitcoins will be on their radar in the future.