I put miles on my GTS, has 30K on it now and I wash the car every time I drive it. Complete end to end with a vac, rims cleaned, tires dressed and leather conditioner.
Thought this foolishness would subside after 4 years but no such luck. I just do not sleep well when it's in the garage not washed. I'd say it has sat unwashed after a drive a handfull of times since I bought it, I've got issues.
Furthermore I hate to drive the car within 48 hours of washing it as the water pulls out of all the crevices and it looks like crap in the first mile, so I don't bother.
Not sure when I really drive the car, hahahaha.....
But when I do, rest assured it's to the tin every time I start it.