Though out the book, everyone is worried about how they are viewed.
Gatsby wanted to look like a "made man" who had it all, and didn't really care how he got there, so he could get Daisy. Even once he had Daisy he had to have it his way, with the Self-Absorption.
Daisy was very much self-absorption, she wanted Gatsby on her terms and didn't want to have to leave Tom. Even though Tom is fooling around with Myrtle Wilson, and he spent a lot of money and time her.
Everyone in the book was focused on themselves and it was because they just wanted to make sure they had the best of everything life had to offer and didn't care in the stepped on anyone to get there.
So the modern example for this American and self-absorption, has to be depicted by Jordan Belfort. Also known as The Wolf on Wall Street. His greed took million off of others to make a life for himself. He has said that he just got wrapped up it in all, that this kind of thing couldn't happen anywhere else in the world besides in America because you're meant to make sure that you fight to tooth and nail to ensure you get everything you want in life.