I would never take my car to one of those places not because of the slavery, more because they do a terrible job and use old rags that scratch the paintwork.
I would also not use a traditional mechanical car wash as those bristles are just as bad.
The only option if you have any respect for your vehicles paintwork would be to do it yourself using decent products and methods.
Yeah, I always hoover/wash/polish it myself. Shiny, shiny, shiny!