Life experience: I've been to many homes in Europe (in 6 countries) and again in many homes in the USA and in Canada. Plus I talked to competent ppl.
That's what I used to say until I took Microbiology at the university level and put this very subject matter to the test. I saw the bacterial difference with my very own eyes.
You'd have to sterilize your hands to be completely germs free and there is no need for that. Over-sterilizing is not healthy either: not every bacteria is going to kill you anyway.
Especially among Hispanics and Blacks.
I don't need to put someone down to feel better about myself. You evidently do. Pity.