I think the point WE makes about bandwagon supporters (re 2004) is bollox, fans come and go, how teams play and perform will 99/100 have an affect on attendances and income, that's only natural. It doesn't define X amount of fans bandwaggoners, it means they are prepared to spend money regularly to support a team/nbe entertained.
it isn't easy for some to watch their team every week (financially) and when you aren't exactly playing attractive or even worse unattractive and losing rugby then fans get disheartened and think there's better things to spend money on.

Yes one could say that with the relative higher income demographic that Leeds as a city has had (since long before rugby came about) over pretty much all the other SL clubs towns/cities alongside the vastly larger population they've always had an advantage.
It shows in the long term success of the club since RL inception.

That said they've been getting very good gates for a long while, that's not only down to fans loyalty but also how the club are seen by their fans too. I also think the way the games are scheduled has a measurable impact, Friday nights for me is almost impossible to get up to Hull from Hertfordshire and for fans living in big cities it isn't always easy to get away and out of 'town' in time for away travel.
Asking fans of clubs to travel for an 8pm Friday kickoff when they are sometimes based 130+ miles away is just asking for trouble in terms of expectation of away support.
Making the travel easier/cheaper for away fans would encourage more away supporters but it needs joined up thinking from all the clubs and the RFL to bring this about as well as a possible away fixture season ticket (blocks of 5 say) and to stop SKY dictating schedules such as the Thursday night games which is having a drastic effect on attendances (& also the recovery imbalance for teams)

I think the traditional Sunday afternoon game has plenty of miles left in terms of increasing numbers & is important to keep families on board but the SKY masters will ensure that we won't ever go back to 1 match on a Friday, one on a Saturday and the rest on Sunday, this alone has had a huge effect all on its own for away support.