The way I see it (and it makes no difference to me as I fit neither category) is that STHs pledge their cash to the Club up front which for obvious reasons will be highly beneficial to the club. You choose for reasons or convenience best known to you, to pledge your cash to the club on a week to week basis, which is still obviously hugely beneficial to the club, but arguably slightly less so.
So, in the highly unenviable position of the club having to make a very difficult decision, I could understand why preference would be given to STHs over fans in your category.