I remember when I was in Australia living for a couple of years.. and all my Aussie mates would bust my American balls about our NFL.
They'd say that we're pussies for wearing pads.
My only reply was, "Because you don't have 300+ pound giants on your fields.. "
This I noticed from attending a few West Coast Eagles (Aussie Rules Footy) games.. they didn't wear pads of course, but they're guys were not nearly as big as a lot of NFL players.. so I imagine the hits aren't as severe either.
Sorry, getting hit by an NFL linebacker is gonna hurt if not kill you.. you better wear your pads!
Rugby is fuckin hardcore though.. but I still don't think those guys are as big as our NFL monsters.