why do girls worry so much about stretch marks while pregnant?

Like seriously, there are so many women that would give anything to be pregnant and can't.. and all you can worry about is "I hope I don't get stretch marks, I already have a stretch mark! Omg guys I got a stretch mark!" It's so annoying... your body is little creating and a holding tank for a beautiful blessing! Who cares if you have stretch marks!? You can still wear a bikini to the beach, why should something so natural that almost every single person has define who you are and what you can wear? 
Sorry for the rant... I've been struggling with infertility for over 4 years now and would literally give anything just to get pregnant and not even think anything about stretch marks..I would focus my energy, time and money on my child instead of creams, ointments etc 
Rant over