If a therapist is paying the owners a %, then of course, the owners have to make a profit. Why else would they be renting the space out. They are in business to make a profit. They need to cover their overheads.
If a therapist is paying rent, then that's slightly different. However, the salon owner shouldn't be left in a position where where they are constantly telling clients every day that they don't know when the tech is in.
I rent a room and I don't do walk-ins because I get fully booked with appointments. Also, I don't advertise or have anything on the front of the salon to say I'm there, so the owners are not bothered by walk-ins asking when I'm there. I make all my own appointments, so I don't inform the owners when I'm there or not as it doesn't matter to them.
There was a nail tech in the salon that I work from and she just didn't get it. She had a big flashing sign on the window, leaflets everywhere, but had hardly any clients. So, she decided that it wasn't worth her while being there much when she could be at home (what????). So nobody knew when she was going to be there. She worked on % basis and couldn't grasp that if she wasn't there working, the salon owners weren't making any money from her. I know it sounds harsh but the overheads for salon owners are crazy and the renter needs to appreciate what they're getting for a relatively small outlay for no real committment.
I think you need to decide which way you want to run your business and have a chat with the salon owner so you're both clear on how you're going to do this. xxx