Oh well, then that means I have this alter ego having a life of his own. Imagine this, after 40 years of having a Facebook account, my shadow account gets his numbers and shadow personality "woken up" into an AI system ( for the Brits, there's a kick ass episode of "black mirror" that illustrates this), I wonder how different my shadow me would be :)
Imagine after the human race ends, some aliens resuscitate "us" by using the principle above from deep buried Facebook archives... How much more bullshit would this artificial human race be made of compared to what there is already :)
From the methods facebook used, I assumed those existed long before they've surfaced to the public so I blocked all thing facebook from my network early on, like buttons and facebook login never had the opportunity to track me as they're filtered out by my firewall.
I started following this trend of blocking unwanted stuff with ads coming to the web (at the time it meant saving bandwidth, money and time) and got serious about it when google stopped being a search engine to an ad agency. I went in full on when google started its surveillance of what everybody was doing on the web outside google (buying urchin and turning it into google analytics).
See this whole thing started with ads which quickly required tools to monitor people interactions with them and it's all been downhill from there.