I am not sure exactly what that stuff is that they spray on the car at the car wash . . . but always figured that some sort of protective coating, be it "wax" or "polish" or whatever, was better than nothing on the car in the winter.
I think you are hearing that too much polish is bad because normally polishing involves rubbing which is removing a little bit of paint, so if you do it too many times, all the paint will be gone. But if you are talking about a "spray on polish" (which seems like an oxymoron, but nevermind) then I don't think there is any issue.
The "no touch" car washes don't do a very good job, but they are better than nothing.
If you can get away with it, take your own bucket and micro fiber mit to the self-service car wash ; use the hose to soap down and rinse the car ; carefully wash with mit like you would at home; then rinse it and apply the "wax" if you want. Obviously you cannot hand wash if there are people waiting in line behind you, but if you go at times when they are not busy you can pull it off.
| 2010 GT coupe | Daily Driver with some Steeda and GT500 take-off stuff for the occasional track day