Two men are in a public restroom...

There is a joke that goes something like this:

Two enlisted guys are in a public restroom, one is Army the other Navy. When they have finished at the urinals, the Army guy goes to wash his hands while the Navy guy heads for the door. The Army guy says, "In the Army they teach us to wash our hands after pissing" to which the Navy guy responds, "In the Navy they teach us not to piss on our hands".

At the risk of turning this into a blog about bathrooms, why do people not wash their hands after visiting the porcelain throne? Whether there for #1 or #2, billions of bacteria are transfered to your hands each time you visit the restroom - bacteria that you're passing on to friends and colleagues. Experiences they may not be willing to share with you will be shared regardless with no concern for people or property.

I rant on this topic after watching a fellow employee use the bathroom and leave with nary so much as a glance at the wash facilities. I know the individual as a passing acquaintance, but am dreading being officially introduced to the man... what happens if he puts out his hand? Should I avoid shaking it while desperately trying to keep my lunch from making a repeat performance? Should I shake then immediately excuse myself to wash my hands? Tough call... What would you do?