Just a heads up, the NLRB has taken an aggressive stance against companies that refuse to allow their employees to unionize.
So when a company has a positive response to unionization, just keep in mind that they don't really have any other option but to "grin and bear it" so to speak.
I agree that when the penalty is a fine, it's just the cost of doing business, but it appears that the NLRB are attempting to go another route.