A large, active membership makes for better gains at the bargaining table.
Cost-of-living adjustments, health insurance benefits, sick leave and the donated sick leave bank, higher salary minimums and pay equity pools, expanded Individual Professional Development Accounts, expansion of the Staff Fee Privilege (tuition waiver), disciplinary and grievances procedures, academic freedom protections...
NONE of this is in the AAUP contract by accident. All of it was fought for by union members who came before us. Only a large membership can maintain these rights and benefits and make forward progress.