Alot of MMORPG's provide free trials. You can get the client for free, and try the game out for 2 weeks, or a month for free.
So saying that you're being forced to pay $50 and then pay a monthly fee isn't always true.
And to boot, the monthly fee is reasonable because you constantly get new content as they update the servers, make new bug fixes, etc. The monthly fees also cover bandwidth.