We're human beings. Emotions and feelings are a big part of how we act or react, why we do certain things i.e. take drugs to party or AAS to get bigger and stronger etc...
We're always looking for "That" thing that make us feel good whether it be looking good for the ladies or being strong amongst your friends etc..
Women do crazy things to keep up, plastic surgeries, Botox, butt lifts etc... It makes them feel better, sexier they mostly do it for themselves.
Same with men. Some use AAS because they like the way it makes them look and feel. Nothing wrong with that.
Some men like to buy expensive toys, cars, motorcycles, expensive watches because it makes them feel good about themselves.
We as humans are the only species that know that one day we will die. We go after "Happiness" which is an elusive fucking curse.
We have emotions that we are not capable of dealing with, thus we act in strange ways. We live in times where too many expectations are pressed onto us, whether to look good, or earn well or be a great doctor or scientist etc..
I don't believe as humans we are ready psychologically, physically or emotionally to be dealing with in general as we're living it. We seek pleasure and self satisfaction from things that either forbidden, taboo or downright criminal.
We race fast cars, jump off planes, climb mountains we do all these things because it gives us pleasure and satisfaction.
So stop trying to comprehend why others do what they do. Be and let be, at the end you either lived life your way or died doing nothing.