Just throwing my hat in the ring. To lots of Welsh, Aussies and Kiwis, football = rugby. Not always rugby union. Rugby league too, especially in the north of England. Dont forget Aussie Rules, which might as well be the only sport in existance in most parts of Australia. Oh, and Canadian Football, but nobody cares about that, not even Canadians.
As for the whole injuries thing, the padding and helmets are paritally to blame IMHO. Players make hits and take bumps in American Football showing no self preservation as they are partially protected by thier gear. Long term this leads to the brain injuries seen in older players. In Rugby, the lack of protection, fewer substitutions and lack of constant play breaks means players have to show at least some self preservation. Removing the helmets and padding might go some way to "slowing" American Football down in order to reduce long term brain damage, but might increase the number of less serious "instantaneous" injuries , but as Rugby has only been played pro for around a decade it will take time to see the long term effects of basically unprotected musclebound behemoths running into one another. I read somewhere (BBC?) that someone like
Jamie Roberts puts his body through the equivalent of a car crash when taking contact, and no doubt this is the same for most American Football players. A few years ago he suffered a fractured skull and played on for 15 mins before passing out. Based on my own following of both sports instantaneous injuries (broken bones, nasty head cuts, KO's) seem more common in rugby (often due to being fallen on by 17 other guys as much as taking a hit) as opposed to the more repetition/critical failure based injuries (muscle strains/tears, ligaments/knees/elbows) in American Football, as might be expected, with the nature of player protection.