It doesn't seem like a tax. You wouldn't call a state government requiring a car to meet some minimum safety requirement a tax, right? At least to the best of my knowledge, no automaker has ever done an "airbag tax".
It's just a political ploy to garner some ill will against regulators and make a few bucks in the process. Seems pretty genius (in a nefarious way) to me.
If you look into it the primary intent of the ordinance is to ensure hotel workers can get help fast if they are assaulted in the course of their job, and the secondary intent is to prevent them from being overworked without consent.
Which makes this ploy especially distasteful in my eyes - bit of a "the city made us make your servants feel safe and valued at work" fee.