I do it all the time too...
Depending on my mood, it's either work clothes, bike kit (not leather), waterproof kit or sports kit. If it needs washing or rinsing, I have fun in it before it goes into the washer....
My favourite is to put a pair of waterproof trousers under my bike kit, leather or not, pee in it when on the bike and just go in the shower when I come home.