This is a distinction without a difference. If I (the NSA) can request yesterday's backups, isn't that close enough? I don't particularly care if they have direct access to Google's servers. Having access to the backups (through sftp or whatever other mechanism) is bad enough.
It's a checks and balances thing. If you're a large ISP and you retain physical control over your servers and network, if you're asked to hand over too much information, it's at least possible to delay and fight it in court. If they have root then you don't even know what they've done.
If they had to request anything from Google or FB, they wouldn't need such huge storage capacities. My guess is that these large companies have been forced to forward data (e-mail, chat lines, posts...) to the NSA as it arrives. It's not "direct access", it facilitates all the searches the NSA could wish for on NSA's own servers and does not contradict any of Google's, FB's or the NSA's claims so far from what I can tell (they store the data, then "collect" it as needed).
