It's no secret North Korea has a pretty big chip on its shoulder. They have to do everything bigger, more ridiculous, and more grandiose than every other country on the planet.
In an effort to prove their superiority to the world (but mostly to themselves), they put everything into that external image. Nowhere is this more apparent than in their armed forces. If we're comparing armies to cars, the Korean People's Army is pretty much the Pontiac Aztek of the world's fighting forces. That doesn't stop them from peacocking their insane special forces on the internet.