You can only clean through two forms of action, mechanical and chemical. Mechanical being touching car washes. Chemical being touch-less. The only way to clean stuff chemically is to use harsher, more acidic, chemicals. Touch-less car washes are what lead to paints drying out and cracking with time. This is why your largest clientele will be people who dont really care for the condition of their vehicle, meaning they are just going through out of convenience. They will not be nice car owners from any car community. People who are into show cars/highline cars will either do it themselves or have a detailer they use. Not to say very nice cars dont go through tunnels, but in all my years(16) of experience, those are generally very cheap owners who dont actually keep great condition of their vehicles.
Also my reference to Sky Car Wash that use to be next to Ferrari of Atlanta is to show you even a high end tunnel system couldnt make it sitting on Hwy 9 in Alpharetta next to a Ferrari dealership. I know a second company came in after Sky and didnt last but a few months. Automated car washes/tunnel systems are extremely hit and miss.
There is currently a national based car meet called Cars & Coffee. Very large gatherings, early on Sunday mornings, where people stand in parking lots and drink coffee.