Morality and human continuation.

I've been thinking about the moral justification for our continued existence on a very literal level recently. Humans, as a collection of mass and a converter of mass into energy, have no intrinsic value over any other collection of mass or energy in the universe aside from that which we assign ourselves - and it seems fairly evident to me that our self-designated importance is just an evolutionary tool that promotes us to survive and breed and continue our species. This on its own wouldn't be very meaningful, we're just more matter floating around in a mostly empty universe, so what? But I think it's when you contextualize our existence within our interactions with the other mass around us that there are some rather disheartening conclusions to be drawn. 

We consume, and we consume a lot. Not just food, we consume commodities, we consume habitats, we consume everything we could possibly find any level of use for - and then we bring in more little consumers into the world to consume whatever hasn't already been taken; And I don't get how that's fair to them. We bring more people into an existence in which they have no real purpose or value, and on top of that we expect them to make do with the crumbs of their forebearers. So what then is the moral justification of birthing more humans? If there's nothing special about us, and all we can do is generate more strife for the next generation ad nauseam, why?