I saw on someone's page regarding the death below, them complaining that is was somehow perverse that people would care, and implied that the people leaving heartfelt statements were just making it up because they were death obsessed… I thought it was very sad to read that, and I really feel sorry for that person. I'll repeat here roughly what I said to them.
I think what you're missing is that for many people this is a community of extended friends; I think it's very sad that you see it so cynically; as just a collection of strangers.
The reason people who didn't know her are sad is the same reason people are sad when a classmate or a family member they didn't really know died.
It's called empathy, and it is very valid, and I'm not sure what gives you the right to demean that, just because you don't feel it yourself.
In all honesty, when a member of your community, especially someone that's young, lively, and full of potential, dies, it's kind of weird to not be touched by it, and even weirder to actually complain about other people are touched by it.