The Argos numbering system

I was waiting for my number to come up in Argos the other day (they actually started playing Tired of Waiting on the shop radio) when I had the idea of making the numbering more interesting. Mine was order number 601, and I’ve never seen one higher than 999. Why don’t they keep going? I would love to hear the computer announce “Number 3543 to your collection point please”. They could carry on for the whole day and see what number they got to. If they did it over a whole year and across all stores, then it would be a handy way to keep shareholders apprised of progress: “Number 2,946,660 to your collection point please.”