No tyre rule
It matters not, even if you have a rule, generally those with newer tyres will do better, so those that need to win club meets generally still will because they will spend the cash on new rubber or additive or whatever.
Until that is someone rocks up and dominates because they're better

Simples, run what you brung, far less stress for the club too

Proof will be in the pudding, as soon as the next big meeting happens, the better drivers arrive, and dominate