Earlier quoted context omitted.
It's different precisely because most social/cloud networks abstract away backups. Very few people have considered whether or not they should attempt to back up their Facebook account. Same's true for Flickr, Twitter, and Gmail.
Frankly I trust Google and Facebook more than I do myself with regard to backups. I know it will eventually burn me, but I've lost, misplaced or misplaced the key to my backups more than once. I'm probably in the minority being so irresponsible with my own backups, but I'm not alone. Google and Facebook have a lot on the line with regard to user trust of their reliability. Also, they can't monetize data that they've…
I'd rather have my own backup copieS and take my own responsibilities. The scenario you evoke here would not happen if you had proper backup strategy, two is one and one is none.