to be honest , i dont think its anything to do with "weeding out" the not so serious ,anyone with a camera taking a picture is taking it for a memory or to be creative ,why do you have to be serious to take photographs ?
I think the fee was probably to pay towards the prizes
as for me i think the whole competition was a compleat shambles ,especially having to pay for it ! no word about the judges for ages after the last photo could be enterd AND i also still think that people "voting" for other peoples pics DID have an influence ,especially the people with nice long "friends lists" on here lol
you got to laugh tho