This is the same problem with the CA Teachers Union...you can opt-out of them taking your money and using it for whatever political purposes they want (whether it benefits the members or not...typically just the union leaders), but the process is very convoluted and difficult to determine and apply.

What I think would be much better is an opt-in strategy but, of course, that would not be to the company's (or union's) advantage.

This would be much better consumer protection: "if you would like to opt-in for arbitration, please contact us by Feb 28, 2013 stating as such."