I grew up watching afl and was entrenched in that mindset, and I find the premise of this question to be unlikely.
no one bought gold coast or GWS memberships to help them out. they didn't need the help, the afl threw more money at them than they could spend. and the lions are not a struggling club, but would have some fitzroy memberships.
opposition supporters have helped out the western bulldogs and north Melbourne to keep them in Melbourne so they didn't end up in Sydney or the gold coast..
the siege mentalists won't get any joy here. only the AFL cares about qld and nsw. fans in Melbourne don't care, and I'd say the majority of afl fans didn't agree with or support GWS' entry.
I don't know why u mentioned the clubs u did unless it is this rugby league siege mentality, because it's simply not right.
membership being easier in the afl I think is partially down to the fact that as a west coast member I'm a true member who has a stake in the club. as a raiders member, I'm not a member at all, I'm a season ticket holder. if I can't get to most matches for the raiders, I don't buy a membership because there's no utility. I don't get to any west coast games in Perth, but am still a member because I get a say in my team (and also cos I can resell the seat for most games
)