I’ll do it to see if I need to take a moment to clean myself during my work day. I don’t want to be smelling bad at work. It’s a habit but it’s also useful. I will also do this with my anus to see if I need to clean back there as well.
I do, indirectly. Usually, I wear cotton briefs and they absorb most moisture and aroma. But, I have this one synthetic pair (no absorption) After wearing them for the day, at some point, I'll go to the toilet and drop my briefs. That built-up aroma makes it's way up to my nose. At first, I didn't like it, but now, I look forward to it.
Guys let’s think about this for a moment. As civilized as we can be, we’re still animals in a way. Animals sniff themselves, they sniff their urine and feces after they relieve themselves. Is it any different for us to sniff our armpits, our socks or shoes after a long day, wipe our crotches or our butts and sniff them? I know that I do all of these daily, how about you?