because skate movies are infamouse for having the worst filming ever.
so vx's suit it, because all their filmers do is point and shoot with basic adjustments like shutter, iris, white balence, gain, blah blah but not much else.
they cant even use a tripod to save their life!
vx's can be good for other stuff, its just that they are the most well known amongst every 14 year old skate filmer who wants nothing more than to slap a fisheye on it and film lowww
of course there are exceptions; some skate filmers are amaaaazing and creative.