I was riding the jumpseat once of a 88 Captain who was a non-member. I cannot quote exactly why he was, he just hadn't paid the dues back a while ago. When the union called they gave him the option to come back whole but it'd be $100,000+ or something along those lines. So it wasn't worth it, so he stayed non-member. Does that sound possible?
Give me a break, it was like 7am on an ATL-LGA commute back in my ER days.