when i bought my 300D new (2 day of release in singapore) it didn't start at 0 either, (around 5000 or 800 I can't remember), I suspect the cameras all under calibration at canon before release thus the shutter count.
besides: must burn in test also what..
I also have two cf cards.
in one card, the number is at 580x right now., in another card it is 80x as well. so it seems I have two sets of running numbers and one day the 80x will hit 5000 and then I will have a numbering conflict with my old files..