actually there was a way to get free subscription for a while. last time i tried it was 2 years ago and it worked. something with using a credit card that had insufficient funds and during the time the transaction was processing you could login, but once you logged off the subs were gone. I don't think it works now but it was an error with their database setup. Your best bet is to find a blizzlike server with no lag and just play that, find a stable dedicated blizzlike and donate and settle into a life of no friends.
Edit: Or make your own server off a repack and make money off donors and VIP. I did it for a bit, was pretty good until another server decided to DDoS me nonstop.