Or you could wash your hands anyways, since it's a good opportunity to wash your hands? Regardless of how clean you think your body is?

That would weaken the immune system...

So you're fine with them touching their sweaty junk and then handing you a donut with the same hands?

Totally! It even adds a pleasant salty taste to the donut!

Hi, I don't want to shake hands with your genitals thank you.

If only that was the only problem.

So you're cool with folks touching their genitals and then touching you?

Totally, especially if it involves sex.