Should You Tip When You Have Laser Hair Removal Done?

I live in a most over-tipped city - New York - and I'm tipped out. If I pay $2000 or more for a service, especially if that service is charging me interest on the loan I got for it, I've gotta, you do not tip when you have laser hair removal done.

After my first laser appointment, I did tip. My technician and I were very chatty, and she was very nice. In trust, I asked her if people tip. She said that I could if I wanted. Of course. So I tipped, maybe $20. I felt like I was in there for so long, and she was literally doing backbreaking work because she leans over the whole time, that I should tip. I had no cash so I wrote a check. Immediately after I signed the check, I felt it was not necessary. I have not tipped since, and my relationships with the different technicians remains in good standing. They don't hover to wait for a tip. They do re-make the bed while I get myself together, but then the zip on out of the room while I race to keep up to make my next appointment.