Why do women spend so much time/money on makeup/eyeliner/concealer when men dont even notice/care!?

I am a girl and I don't spend tons of money on that crap. My boyfriend loves natural and so do I. I am a predent student and don't have 5 hrs in the am to get ready but a lot of girls have terrible self esteem and hide behind their cake faces but not all girls are like that. I think they look ridiculous too a little makeup here and there is all you need looking like you took 5 hrs to get ready just is not attractive.