Maybe they are all someone else's sockpuppets. At a given date, they will coordinatedly change some whitespace in their comments (but not the hash itself), thus framing Quirrell. Fortunately, now that I unmasked the plan, it is not really viable anymore.
I would like to make a prediction, but I'm not ready to raise the subject of the prediction just yet. So to show that it was not just obvious in hindsight, and to strengthen my precommitment to write an article about it later, here is the sha1sum of my prediction: 9805a0c7bf3690db25e5753e128085c4191f0114.