I don't think you can compare a money value of a MMO to other forms of entertainment like bars or baseball tickets or cable TV. But you can compare it to other videogames maybe. Like I'm spending more money now than when I played FFXI on videogames. That's a fact. I played FFXI on a standard def TV, on a fat PS2 with a $10 keyboard and barely bought any PS2 games.(Most of my PS2 I bought afterwards, used, and haven't had time to play them... shit I want to own to be able to play like Persona 3, ext.)
Since then I bought a PS3, a 360, a Wii, a high def TV, an expensive 7.1 receiver and speakers, over 100 blu-rays, about 50 PS3/360/Wii games, a projector, a PSP, about 10 PSP games, some old PS1 games, some PS2 games to collect... some old xbox and gamecube games, tons of extra controllers, a $50 xbox gold card, like 20+ PSN/XBLA games...
And honestly... gamewise... time goes by faster when you are playing an MMO. I wasn't sitting around waiting for FF12 like I am for FF13. In fact I didn't get FF12 until a few weeks after its launch cause it wasn't so big a deal. For someone who doesn't play an MMO, I'll be there first day to get FF13. There are a lot of (great) games I wouldn't give the time of day. I wouldn't touch games like God of War, Ninja Gaiden, Heavenly Sword... I wouldn't have bought Saints Row 2, Burnout Paradise... I'd have skipped even shooters like Halo 3, Killzone 2, Rainbow 6, COD4... and pretty much the only thing I'd play are big RPGs.. I mean Final Fantasy and Kingdom Hearts not even Dragon Quest or Star ocean.... Smash Bros and the Socom/Timesplitters for shooters.
Of course it also means a giant time sink of time in my life I wouldn't normally be playing games during. Like you don't stay up later than you want to leveling up in a single player RPG. So I'm glad about this increased emphasis on casual play. I just hope it doesn't add complications if you want to play when specific friends. Like if you sync out with them level-wise.... once you start to static with them then you feel obligated to be there when it may be to your personal detriment.