What most people don't realize though, is that Injustice has 2 big components of the audience:
1) People who are playing it because they played MK and Injustice was the next game by the same company
2) People who didn't play or care about MK, but like DC comics or found Injustice appealing because it's a cool game and has crossups and other such mechanics
I think that no matter what, some people will only like Injustice, some people will only like MK, and some people will like both. But we can't act like it's all the same group of people and they will all jump ship no matter what.