Begs the question why?
Must admit sometimes I go through precious phases and persuade myself:
1). It's a PITA to keep darker colours clean- looks like it's got chicken pox after a few drops of rain,
2). It's good for keeping the mileage down,
3). I'm less likely to bin it.... my skills in the wet need a little 'polishing' (although that doesn't improve if you just avoid the issue, obviously

)
The first one is just vanity/laziness. The other two are more pragmatic in that if I bin or break it it I ain't got the funds to sort it just now...
But mostly I don't give a toss, don't wash it, and take my chances with the undergrowth. Couldn't last a fortnight, regardless of the weather.
Next time it rains, get behind the wheel, and start her up. If you can resist grinning and reaching for the gearstick, sell the thing.