From seeing it here it's like annual sports games, where fans buy them every hear to play with friends. As for coop game it is important for kids to have newest iteration, because everyone will be basically "done" with the current version for like 2-3 months.
The head of coop game is obviously Monster Hunter, followed by bunch of similar or dissimilar coop games. Enthusiasts aren't satisfied by just finishing Monster Hunter and thus purchase GE, SS and such... and of those bunches Toukiden did quite well for the first shot.
Is it similar to annual CoD and BF thing at the west? I can't really tell...
Yes, sports games are kind of similar but there isn't really much you can change with a sports game. The core gameplay is set in stone and it is not like they can make new enemies, levels or a story mode. The meat of the yearly updates are the new rosters and finetuned gameplay changes. I myself am guilty of buying a Fifa every year on day 1 and maybe even a PES.
Your shooter comparison doesn't suit well though. First of all, Battlefield isn't a yearly franchise so far and secondly, I feel these games do offer new content (campaign, nearly only new maps in MP) compared to the expansions.
Furthermore, the way he hunting genre handled expansions was because of the platforms they were on. Those games hit it off on the PSP where DLC wasn't a good option. Now with the new devices, adding a DLC option for upgrades should be viable.