rugby players dont want to sacrifice their futures, they just have the common sense to tackle properly, so therefore dont need a helmet.

any big lump of a doofus can run at a guy and hit him hard, provided theyre protected with pads and stuff
no rugby player would go in with his head. and no rugby player longs for scarring. if it comes then fine, i dont mind cuts and bruises

and the fact that the football players have worse injuries (despite having protection) just prooves they are idiots who cant tackle