Im sure events will always exist that do not require entry fees, whatever happens with some organizers. I think its difficult to justify one organizer paying fuel, hotel and appearance fee when other pay nothing and charge you to enter.

Im from a motorsport background and think the roboteers have been spoiled by having things free, as it cost me fuel, hotel, entry fee, club membership, tyres, etc etc per event, but I cant see it changing now without serious probelms, its been free too long.
(for free read expenses paid)