I can say that there are quite a few of my friends who play both rugby, soccer, football and hockey. They all said that hockey and football are the most intense. Rugby and American Football are very different sports in the way there are played and the tackling style of rugby doesn't necessitate the use of pads. Both my friends who play football and rugby said that they have never felt in danger of injury in rugby. Don't get me wrong, Rugby is an extremely rough sport, but you don't get the same way as you do in football. I'm sorry, but this doesn't happen in rugby.
The part I don't understand is why do people still watch it even if they hate both of the teams? This is like having a gigantic party and inviting the neighborhood just to watch the Indy 500, even though everyone in the neighborhood including you hates the shit out of everything Indycar does.