There are probably some legal issues too, like how a game can get a yes from SCE Japan and a no from SCEE. Most publishers do not have branches in all major regions, some strike a deal with another publisher (NISA and Koei), others just don't bother (Working Designs). And Square Enix Europe just plain sucks, but we know that by now.
Or Disgaea. I actually enquired with the European publisher if it will be like the US version... and it's not.
50Hz pal-barred and NO JAPANESE VOICES. When I asked why he said because SCEE didn't approve that O.o
PAL releases, pshaw. Only rarely are they better (see FFIV Advance).