Most if not all of the club sites are owned or rebted by the club. The wardens are employed on a salary from the club. It cost them personally nothing to allow someone to empty/fillmup with water, but does cost the coub something.
It seems that the cost of providing water and possibly black waste disposal would have been consideraby less than the outcome from debates like this when people discuss their disatisfaction wiith the "Club" and vow not to subscribe or renew membership.