I dunno. I've laughed at some huge jerks over the years (the most offending one being the Annoying Devil, probably), but this particular prank just seems petty and uncreative enough that I sympathize with his victims.
If he were protesting overfishing or something (I can't tell, seeing as I don't speak or read French), it'd be marginally more cleaver, but then why is he targeting recreational fishers and not enormous commercial fishing corporations? He could do better.
EDIT - His Pac-Man video was pretty funny, though.