Running a club is, for the most part, a PITA. People don't do what they say they will do. The best advice I can give is to make it very clear to everyone that membership entails obligations as well as privileges. For example, at one of my clubs every adult member had to commit to assisting at at least one event every season - marshalling at a road race, helping out at a TT, taking the money from on-the-day entries at a crit, whatever. Anyone who failed to honour that obligation was not allowed to rejoin the following year. That didn't stop some people from welching on the deal, but at least it meant that welchers didn't stay around.