If the parlour does not have a receptionist then the least they could do (and a number do this) is have a white board with the gals on that shift and the time the next gal will be available.
It is better than being on time for your appt, being told the SP is ready and will be right in, and then waiting 15 minutes.. I was actually tempted to dress and leave. With the session I had, I wish I had done that...
I'm surprised you were able to get in the door with nobody there to meet you. Any place I dropped by here ( Vancouver Area ) you have to buzz to be let in and you be sure somebody will be on the other side when you step in.
Very few MPs have locked doors here. Jaileys is the only one that comes to mind. I guess we are generally a more trusting bunch here on the prairies. ;-)
Actually, if the MP has no receptionist and all the SPs are busy then at some places they do lock the doors (case in point - Kings Court).
If the MP has a receptionist then there's no excuse to be kept waiting for a greeting.