What is there to explain? People want to get Bitcoins... This does not mean anyone's greedy neither that people who use Bitcoin are more greedy than people who use exclusively fiat.
Bitcoin represents many things fiat does not. But neither represent greed in its essence, not even fiat
the sad thing is that they see bitcoin as a quick buck scheme, and they want those coin to dump for fiat and by cigarette and say to their friend that they made easy money to internet, and bought those cigarette with it...