The last MTB club I was in spent money on:
subsidising club kit
subsidizing race entries
subsidizing trips through the UK and Europe
Buying a club van
buying various bits and pieces of kit eg. bike lights for use by members, club generator etc.
Organising road races, xc races and sportives. (which was the biggest recurring expense)
income came from:
membership fees (£20)
race entries
sponsorship
Although membership fees were very important, the biggest earner was road race entry fees though the club struggled to break even on XC events. Sponsorship was meant to cover the cost of subsidized kit, but rarely did.