If employees get "hardcore" about creating limits on how the company can hire/pay/whatever, it obviously changes how the company engages with those employees as well.
To wit, if you force me to sign in blood for everything I have to give you, I am not going to give you anything else.
This isn't the union failing to negotiate a good deal, or being sticklers about procedure and thus preventing union employees from getting what non-union employees are being given. Starbucks is deliberately using this as a way to sabotage the union, by refusing to even offer them the same terms as non-union employees. This is illegal.
Since the terms are already different, how do you compare if the union rate (no CC tips) is better than the non-union rate (with CC tips?)
It is painfully clear that this is a deliberate union-busting tactic on Starbucks' part. The only reason they gave any stores these benefits is in order to make the union look bad.
This is illegal.
Remember, the employer/employee relationship is an inherently unequal one. The freedom of the employer to do certain things is curtailed for the common good, in exchange for substantial power and economic advantages.
Just sounds to me like they don't actually have the leverage they promised their members to extract better pay, and are now whining "no fair" for having to sleep in the bed they made.