well, clubs are required to have their club MEMBERS be members of AMA,
not that AMA mandates that clubs require AMA membership to fly at the club site.... they just (obviously) dont have AMA insurance for that

and that is the double standard that LCS is talking about:
Folks get all uptight when it is suggested
that non-AMA members bring their own insurance and fly at ama clubs without AMA insurance

Yet the same folks dont see anything wrong with
commercial/demo/etc pilots bringing THEIR own insurance to fly at AMA clubs without AMA insurance