I think all teams should employ the "paid up members get selected first" policy.
If your struggling for a side etc, then sometimes turning a blind eye may seem okay. But if there are players blind refusing to pay but it's obvious they have money(usually as they show off how much the spent down town last night) then I think I'd rather play a few men down then pick those sorts.
Remember clubs need money to survive! Not all clubs have a silver spoon in there mouth.
If you genuinely can't pay(money issue/jobless/student/emergency reasons) then discussion with your club and I'm sure they will be willing to help out in someway(monthly payments, small deduction etc).
But if you've got no money because you've merely spent it all, well you don't have my sympathy as the club fees come round the same time every year. It doesn't take a genius to plan it into what you need to spend that month!