Dublinpilot, you are correct, at least to the extent that there is an argument to be made.
However, an argument can also be made that everyone benefits when a pilot's safety is increased (if he or she is incapacitated - which can happen in circumstances other than a crash landing - who will fly the aircraft?). It is hardly unique for aircrew to be furnished with better equipment than their passengers. E.g., the pilots of most (all?) commercial airliners have much better safety harnesses than the crummy lapbelts back in the cabin, and (I believe) air ambulances do not typically provide their patient-pax with helmets.
In any case, personally I wouldn't let the possibility of an adverse finding in a potential lawsuit prevent me from wearing safety equipment that might save my life ...