I think you are being a bit generous on the production numbers, "a few thousand of each title".

If we classify that list into A list, B list and so on, most of the B list titles and below would have a total production run of about 1200 units at most (produced once and then shelved forever).

As an extreme example, CSI and 24 both around 500 units each and 99.9% likelihood will never be run again.

I'll go further and say there is not one title on there that has cracked the 10,000 mark.