Well, believe it or not, it is a coincidence.
I see where you are coming from, and appolgize if this was interpreted the wrong way.
The truth is, some of my relatives were buggin me with this question all last week and I couldn't find any satisfactory answer on the net, so naturally I posted it here. <img src="/images/graemlins/laugh.gif" alt="" />

Thanks for all the responses.
I suppose there are instances when coin cell batteries are superior to AAAs etc, for example in such flashlights as Photon, and Inova, but I am still not converted as far as the bigger lights go.
One argument I agree with is that of Brangton. He mentioned that during an emergency there will be a run on the stores to get all the AAAs etc people could find, but 123 may remain untouched. And of course that of specialized applications, when density is more important then the duration.
I realized now that I should have posted this in the long term prep forum. Sorry. <img src="/images/graemlins/blush.gif" alt="" />