Why? We are only a little blip on the time scales that nature works in. Why are we so arrogant as to think that we are the only life in the universe? It is very likely that we are not and even if we are, there is always a chance that life will arise again.
I am a nihilist and don't really think that this will affect my life. I suppose that is most of my reasoning in not worrying about things like this.
Edit: Messing with it now will affect my life due to the proximity in which I live to Yellowstone. If the park gets messed up and tourism declines, my local economy will take a huge hit. That is something that can happen in my lifetime.
You live near the park, then? If you don't think getting buried under 10 feet of molten ash will affect your life, I really don't know what else to say to you.
