I get what you mean, but so far that's only a just in case thing in relation to a tyrannical government rising up. In the mean time live ammunition is often used in all sorts of situations such as robberies, gang violence, rage moments and many more.

It's just that I think it's overkill when something as rubber bullets can achieve the same thing as live ammunition, minus the many deaths.

True, but in many cases I'd think that the assailant has the advantage of surprise to kill someone, so it doesn't neccesarily have to do with the type of ammunition. But if the amount of violence happening can be lessened by the limitations of less than lethal ammunition then I think it's a good thing.