So, the only way for my kids and I to play co-op - IN THE SAME HOUSE - is to buy 2 copies?
I have my digital downloaded copy, installed on both our Xbox One’s but on the 2nd one, even though my Profile is on it - under the kids profile it wants a 2nd purchase and the game won’t launch.
I guess if I buy it again for them, it will work online as my profile provides XBL onto that 2nd console, but I still think it’s crappy that we can’t play co-op unless we buy 2 copies of the game 
I think next time i’ll just buy it on disc, at least that way they can borrow it to play whenever they want - when I’m not using it that is.