Once, I saw an article I thought reddit might like, I checked no-one had posted it, but then when I did it said some-one had done (that very second, by some-one who posted frequently, but not from that source). The article was hours old, so I wondered if some of the karma-stealing was automated to favour certain users. Probably just a coincidence, but it's nice to get out of 'but what about my karma mindset?'

(For any worried readers, fear not - I posted a comment in the guy's post which got about half the karma the post did, so all wasn't lost)