I think in that climate you would have to either use a waterless wash in the garage or find a touchless wash or use an automatic carwash. It needs to be done, however like I said its less of an issue if the vehicle sits outside because the corrosive chemicals are inert.
The answer is...its better than not washing it.
However, touchless high pressure washes use harsh chemicals that themselves can stain the paint and dry out black trim, etc. Automatic washes use similar chemicals and those cloth strips are abrasive themselves and rarely cleaned.
My advice, if you want to take the best care of the vehicle but don't want to wash it yourself, I would have a mobile detailer wash it for you regularly. Won't cost a whole lot more than the automatic wash...