I want to know why people do this..?

This is especially with "skaters". I noticed that "posers" (People who say they skate and ****, but can't even push the board with out smashing their faces.) tell beginner skaters to **** off and stuff because they can't 3 flip on there first try. Or act like brands like Airwalk, Vans, and Shaun White brand shoes are not "quality" shoes, because people who don't skate wear them, but, I've skated with all three, and I like them way better then DC, DVS, ect. I find it ridiculous, so what gives people the mentality to do this.