Do you do this too?

Hello and welcome to my submitted Post.

I'm from Germany and watched our national team play yesterday.
And because it is the europe championship, there are more than a million cameras and a few catched our sweet national team trainer Jogi Löw, when he rubbed his fingers between his balls and smells them.

So, I find this rather disgusting than interesting.
Now I want to know, if some of you do this too?
Is it normal?
Why would you do this?