It activates the same chemicals in your brain as cocaine! 
Well, yeah, there are only ~~three~~^[@Neuromancer49@midwest.social corrected me] a few neurotransmitters. That's not saying much.
You know what else activates those chemicals? Practically everything. When scientists breed "knockout" mice without dopamine, the mice just stand there until they die of thirst, because there is no reward for.... living.
It contains more germs than a toilet seat! 
Germs like moist surfaces. We don't want germs on our toilets, which is why we make them out of porcelain, which is hard, dry, non-porous, and easy to clean.
If it had more germs than your colon, then I would be concerned.
They're stinky because they're not running to their full potential as you pointed out so they're constantly running rich. They don't burn off all the fuel they're designed to so their exhaust stinks!