Personally, I don't have enough time to support more than one team. If I had any more spare time, I'd go to more Derry games. I'll happily watch football anywhere in the world but I'm never too bothered about the results, its more about the experience.
In terms of why the Irish aren't more like the Cypriots or the Norwegians, who tend to support a British team but also go along to their local games as well, I would say its a combination of reasons. In no particular order,
1) poor facilities. Its a good reason not to go, particularly for those with families
2) Lack of FAI support. The FAI didn't give a monkies about domestic football until recently, and arguably they still don't. This don't care attitude goes back generations and then has propagated in the media and onwards to the wider sporting public.
3) Bandwagonism. As a nation, we love jumping on a bandwagon. There are numerous examples. Basketball in the 80's, rugby in the last decade (interprovincial attendences were similar to EL 15 years ago). We don't have a culture of supporting a team through thick and thin. The GAA is based upon a small hardcore keeping the sport ticking over for 9 months and then a crowd of yahoos rocking up to Croker in the summer. Supporting multiple teams allows you to hedge your bets and increase the chance you can catch a passing bandwagon.
4) We're really still British. Unsaid, unaccepted, but true. We watch their TV, used their currency until recently, shop in their shops, use their language, still our biggest trading partner. We're even siding with them on Europe. Why wouldn't we support a British team?
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