Can someone please explain why so many bicycles have a straight piece of pipe for handlebars?

As far as the human body goes this is all wrong in that these bars twist the arms 90deg. out of natural normal position. This places pressure from the shoulders to the hands with the wrist taking a real beating.

It goes without saying I won't/don't ride any bike with a straight bar but millions do considering how popular the various recreational bikes & dirt bikes are sold every year.

Don't people get that these cheap azz bars are going to become uncomfortable after a short ride**********???