Some dealership's labour rate is already around $140 per hour. Of course, this is not the exact rate paid to individual technicians, but I have not seen people tipping at any garage yet.
Although, in movies, I do see rich people tipping everyone everywhere generously - I don't see problem with that
Depending in dealership, some dealership pays about 25% of the shop rate to individual mechanics while some high end car dealers pay them annual salary.