Absolutely. Although from a Gaelic Games and Soccer background, got into Rugby Union and NFL at almost the same time, aged about 11 (watching 6 Nations and Ch4 NFL with my cousins) Bizarrely enough became a huge cricket fan at the same time (long school holidays and limited TV = Test Matches!) before an Ireland international team technically existed (it was a representative 'county' team under TCCB). Got into League thanks to Martin Offiah's generation, and although the League-Union rivalry made me smile, being Irish I never quite 'got' it, because I liked both (and NFL!) on a sort of continuum. And then watched my first Grey Cup at 19 - personally, I prefer the rules of CFL just because it's a more expansive game, which may be a rugby fan overhang, come to think of it...
But yes, you start with the Touchdown - why is it called that when you don't have to actually try to touch the ball down, where as in rugby, you don't only have to try to touch down to score a try, you actually have to touch down!). The 6 tackles v 4 downs is parallel evolution, I think. But yes, rugby League is basically ironman NFL without the forward pass, so everyone becomes, literally, a running back!
FWIW I've a couple of American friends (and several Canadians from Uni!) who are late but absolutely mad concerts to rugby, precisely because they cottoned on to the idea of a speeded up NFL with no breaks - they just consider the sport brilliantly barbaric!