I don't believe you're correct in your statement above, but maybe I'm reading it incorrectly. The union, in this case ALPA has a responsibility to represent any pilot, other than probationary pilots, in labor-management disputes, regardless of whether they are paying a "maintenance fee" or not. We had that very situation happen a few years ago at FedEx. I believe the pilot in question, a non-member, got himself into trouble and was either fired, or given a bunch of time off, with no pay. The union went to bat for him and lo and behold, he got his job back. Needless to say, he's now a fully paid-up union member.