And that employer agreed to make his shop a union shopWho cares? I'm doing business with an employer, not fellow workers.
Thus agreeing to a union shop if you agree to work thereI shouldn't be forced to join some group of the workers when I'm agreeing to be paid for my work.
No its not. Additional arrangements are put in all the time in contracts.Adding on different memberships to the employer arrangement is illegitimate nonsense.
There is clear merit; you just accepted a job where the contract was agreed upon by a collective bargaining force.It's like, hey, you want to join my club and when I say hell yeah, you say I have to join another group that fellow club members founded that I may or may not be interested in. There is no real merit to such nonsense.