Maybe they're using "flagrant" differently than the rule book does but I didn't see any here. Hard fouls, yes. Possibly "Intentional" (difference in the rule book) but probably not flagrant.
#1 was a big swing but I'm not really sure he hit him that hard
#2 isn't any worse than you see in about any game.
#3 looks really bad the first time but when you watch again, he doesn't really even hit the kid and stops his swing (doesn't swing through like he was trying to hurt him)
#4 should definetly been an intentional foul but not flagrant (flagrant meaning disqualification)
#5 would be the closest. Again, I would definitely call it intentional. Since they all seem to be in the same game, I would be getting pretty suspicious by now but by itself, I'm not sure about flagrant. The big thing to me was there wasn't a big swing or push. It looks really bad but he just stuck his arm out and is a much bigger guy.
#6 is again not much different from what you probably see every game
All that being said, I think "thugs" is a pretty apt description. Most of that stuff by itself isn't worthy of throwing a kid out (which is the consequence of a "flagrant" foul) but, if I was the opposing coach, I'd be having a good conversation with the refs. I don't think there's any question they are trying to be really physical - beyond how the game's supposed to be played.