always get the impression with that that it's become vicious in an attempt to legitimise itself, as stupid as that sounds
southampton - pompey the same, like they're out to prove how much they hate each other instead of actually wanting to win a football match & bragging rights
Hmm. Yeah, maybe. I don't know much about the south coast one, but I've lived in north London. There I think loyalties are somehow a bit more diffuse just because of the kind of place it is. In Newcastle, pretty much everyone is black and white. In north London, people come from all over the shop, and football rivalries become less visible in the multiculti confusion. But they're serious games.
South Coast all stems back to dockers strikes and the Southampton dockers breaking it IIRC.