"For me, political parties aren't like football clubs, you don't pick one and support it for ever."
Indeed not - the White Paper thread has covered a bit of that. Whilst I do not exhibit slavish devotion to any single specific colour of rosette there are still some parties who will never ever get my vote entirely on principle, even if hell were to 1: start existing and 2: freeze over.
Do people get to pick their own association shoutball clubs to support or are they coerced into supporting particular ones by peers and parents and domestic locale?