Well, as a dad who has 4 competitive boys, all of whom play sports, this is an issue. I also coach soccer, and dadgum if there's not a sissification of government (county)-controlled sports.
So I endeavor to teach my kids to love the game, and that winning IS a great thing, but to be an excellent sport when they lose. Kind of subversive in a way. Finding a way to keep competitiveness alive, but not driving them to "slaughter" the other team just because.
It's ok for the Patriots to do so because these guys are pros. If you can't stop Tom and company well, sorry. It's the game.
So I've tried to instill this in every team I've coached. Even within these leagues you will NEVER stop some kids who have kill-or-be-killed mentality. It is tough. I have to step back every so many seasons and stop just to regain sanity. And then I have to absolutely muzzle my mouth when I'm on the sidelines and my kids are on a crap team with a parent who's never coached the game and wants everyone to cheer when either team scores.
I do teach my sons to be agressive *on the ball* and to play to win. Fortunately one of our boys is on a travel league now where competition is praised, but so is sportsmanship. We do encounter jerks on other teams, parents can be especially nasty.