Short rant, because some people lie and act surprised and even offended when I tell them they do it too but don't want to admit it. And that pisses me the fuck off.
This is something I do on a regular basis, like all other men* (yes, you too), and that is: smelling their fingers after scratching their balls. This is a perfectly normal thing to do for a man and it's the best sign of whether you should shower or not. I take pride in the ancient tradition of ball scratching and then smelling my finger only to smell - nothing - or in the least, the body wash.
If you deny this, you're either not a man or full of shit.
*Notice I said "men" and not boys