They say that because rugby's a rough game that started at private schools, but it works the other way around as well.
Rugby's the posher sport that allows (or demands) more thuggishness and barbarism on the field.
Soccer's the popular game of the masses, that (at least in theory) requires a little more restraint on the field (if not in the stands).
agreed, this year for the 1st time in 6 years I get to play in a league match against one of my best friends, he fish-hooked me while on the bottom of a ruck back in 2004 while we were on the same team, I keep reminding him of pay back! in 2 weeks it will happen, then we will all go to the bar drink, and brag about it!