I agree that this is probably the case for the Leckie quote and also that I was therefore being a little unfair but my grumble about that (ab)use of 'so' still stands!A lot of writing is -- as would seem to be the case with the Leckie examples -- simply the writers' speaking voices written down, not the way they'd write prose or even dialogue**. As such, I think it's forgivable: most of us don't edit our speech, as it's produced instantaneously. We can, however, choose -- or train ourselves -- not to be upset by it.
** - Dialogue is, generally, tidied up speech.