OP, depends on your color. I live in Florida which has awful sunshine and rainstorms year round. I am fanatical about cleaning my car weekly at the minimum and I have had my car for over 2 years. While I wash with water and soap 90% of the time, I have starting using extremely soft beach towels and high quality micro fibers and over lubricating the paint for a "waterless car wash". My silver paint has never looked better and I have been tracking scratches under gas station lighting at night (which is deadly) and while this may not be the ideal option, its been sufficient so far.
Point is, if you car is a little dirty and you have one of the lighter colors of our car, don't beat yourself up if you use a really high quality 1/2 & 1/2 water and detailer mix and a high quality towel to clean your ride in needy circumstances. These aren't 1920s fords in a museum where the paint needs to be treated better than human life. Take my advice or leave it but I have preformed a waterless wash on my silver in extreme circumstances and it looks fabulous.
Just my 2 cents
