The same here ,I tip between $25 and $30 ,because even there is not HE. the girls work hard for the money,doing real and good massage is not easy job and they don't make much money,so they deserve good tips.Some cheap customers tip $2 or $5,that's crazy considering the good and professional massage they are getting,and the prices so cheap for the services.In your case,I guess if you gave a good tip, the receptionist think something that is not allow on a legit Spa is going on.I always tip directly to the attendant to avoid bad interpretations.