I think there is something to be said for just getting clean and killing germs (which is one of the things soap does). I have a compromised immune system, so I am very sensitive to the whole germ thing. Often, the best way for me to break a fever, get to sleep after hours of insomnia, etc is to shower. I am keenly aware of the impact on cognitive function of being even low-grade ill, something other people seem to largely be oblivious to. I don't think that means it doesn't impact them. I think it means it impacts them less and they are unaware of what is causing them to have an "off" day.