What's strange about it? Sedo will insert bid-less names into the auction if they think they're valuable enough. Being from the same seller, the names would have listed at the same time and an interested party could have stuck an initial bid in quick-fire succession on each one. I do that from time to time - scan down the auction list and then stick bids on 2-3 names that caught my eye, bang bang bang!
It's hardly beyond the realm of possibility, that's for sure. I doubt there's anything "sinister" going on...