T doesn't have a waiting room as he works from home, so I make sure I get there bang on time with no hanging around outside or in the car. But it wouldn't matter either way, as I manage to shut down by the time I get there anyway. Not that there haven't been times when I'd have happily turned tail and run away (mainly due to cock ups on his part before start of sessions.)
I've only ever seen one T who had a real live waiting room with a real live receptionist, and I have to say that that contributed even more to my shutting down, making small talk with the people who came and went in the waiting area and reading whatever magazines were around - not conducive to putting me in a therapy frame of mind. Too clinical for my liking.
But I did get to use the loo without feeling so embarrassed about it as I do in T's own home...