What is the official reason for even having region locks in the first place? Who is responsible for them, and what purpose are they supposed to serve?
IIRC for the 360 it's up to the publisher, though MS might "suggest" it for certain titles.
A big part of the reason people still use region locks is because they're hopeful that a foreign publisher will buy the rights to publish the game in other countries. If everyone everywhere can play the game already, it removes some of the incentive to publish the game in the foreign market. For some titles it's not a big threat, because the language barrier makes imported versions almost worthless to the majority of the population.
But in the case of Cave games, there's a fairly small userbase and little to no language barrier to deal with - making imports easy for these titles would kill any interest a foreign publisher has of picking it up. And while it seems like Cave would do well to just take the extra 500 or so sales (I'm pulling numbers out of my ass sorry) they'd get from a region-free release, if they can get a publisher to pay even $20k for the rights they'd make a similar amount of money with almost no additional cost. The $20k is just an example - I'm sure Cave is asking for a lot more, but it gives you the idea of how a small licensing fee can offset a few additional sales pretty quick.
I don't know that Cave really needs to be super concerned about network play being effected by people from other countries since I don't think multiplayer is really a selling point for any shmup. And in any case, regardless of a region lock people outside of Japan will play it. Assuming it's not a bullshit excuse, maybe it's a good sign that they're trying not to settle for anything less than perfect.
It's a bit disappointing with the current generation, because region free
is a possibility this time around. Still, as someone who paid $250 for a JPS2 (twice, lol console life concerns) I can't say that it's a deal breaker for me.