You don't need to use any chemistry for shower unless you are greasy, thus no pollution and washing your skin with just water is good for it if not outright neutral. You do you, some people sweat and/or smell more, some people less, some have very social lives and some go out of their home just for shopping or not even that.

And some simply don't care if they disgust others. World is big, no need to bash Americans or any other nation.