I know that there are exceptions to every rule, but......
As a rule, these hand car washes want to get as many vehicles through each day at minimum cost, with the vehicles coming out very clean.
The best way to do that is to use harsh chemicals that strip traffic film and road grime off efficiently. The trouble is they are harsh on everything, stripping off waxes and sealants as well as dirt.
I only trust myself to wash my cars and van, at least if I cock it up I know who to blame! Anyway, must go, apparently there's a rush on peanut butter at the shop.......