Yeah it’s an MMORPG, 99% of them use a subscription service. I’m goign to use WoW as an example even though we are kind of comparing apples to oranges here.
WoW has been around for ohhh 7 years now? Has had 4-5 expansion packs that have added shit tons of content, and on a weekly basis they fix things and tweak the game to make players happy. THey have also been able to update the graphics a bit, while its still dated looking compared to say RIFT an MMO that came out a few months ago, its still a beautiful game
Now, there are 11.4 million subscribers to WoW, now this is not accurate because not all these subscriptions have been active for the 7 years, but if they were thats 14.7 Billion Dollars on the subscription alone, not counting the 5 expansion packs that were 50 dollars a piece new, and that if you want to progress passed certain points in the game you must own all of them… SO needless to say they make a SHIT ton of money
Battlefield/Call Of Duty, could and probably will do a service such as this, you pay a monthly fee, for that you get lots of updates as now the game devs have a little more incentive to fix these things, you will get expansions and content. As far as graphics go, most games use the same engine for 2-3 years anyways so thats not so much an issue… if a single COD/Battlefield game goes STRONG for 3 years before the next is brought to light, thats a sucess IMO, because these days it seems hard for some games to live past 6 months if that.