The Maneater - all those years? (SPOILERS)

So, if it was the old Indian, what did he do all those years? (I assume that, because he is 75 in real life...his character looked 60+ easily). Has he been doing it since puberty?

Or........did he just start "Maneating" when Cain showed up? For all the folks he killed, he would've wiped out the whole town if he'd been doing it for years. And, if he went out of town, (or came in from another town) I would think there would be some pub?

Doesn't make sense? When did he start? Why did he start? Man Menopause? lol