Your 'friend' and her copycats think they are somehow entitled to that traffic, which in the long run is responsible for the famous eternal September feeling that many websites have.

Gaming the system is like the internet equivalent of slash-and-burn agriculture.

I don't care whether it works or not, or whether you consider it justified because her content was good I think it sucks.

If you want to have that traffic start your own social site, promote that and make it work, then feel what it is like to have people come out to game the system and use your knowledge of how such systems can be gamed to put a stop to it.