Anything that protects people that want to work from unions is a good thing.
Unions at one time a good thing are now basically a ponzi scheme that gets non worker a wage from the earnings of a person that actually did the work.
Right you are. Up until the late 1930's unions were usually a very good thing. Conditions in most factories were horrible, dangerous, and dehumanizing.
But now the government has protections in place (worksite safety laws, anti-discrimination laws, etc). This really makes most unions unnecessary.
But beyond that, it's all about freedom. No one should be forced to join - or financially support - any organization if he doesn't want to.