I'm the kind of person who, when given a choice in-game, needs to constantly force himself to be the bad guy.
Morals apply in games, just not to the same extent they do irl. As for to what extent, that probably depends on the person.
Well what I heard was that its power comes from it being constant, it doesn't matter if the universe is a meter wide or a trillion light years, it still expands at the same rate due to dark energy.