Many business in Massachusetts either have signs in the windows asking you to leave a Google review or at the end of the service ask you to leave a positive review. This has happened to me with tours, moving companies, at barbershops, laundromats, tailors and restaurants.
I don’t think it’s unethical but a requirement of a successful service business to ask all its customers to leave review, as long as the company/employee isn’t asking for the review quid-pro-quo.