[Al Skierkiewicz]

Andy, Greg, et. al.,
You would be surprised at how much that little AA cell can deliver. (Anyone out there drop a 9 volt battery into their change pocket?) Just check out DC-DC converters at the MAXIM website for data on how to get 5 volts from a chip and a 1.5 volt battery. Yes you are correct that several battery strings in parallel would be required to deliver the current of our battery. Now here is the killer... Batteries wired in parallel will deliver current from the more charged battery to the less charged battery constantly alternating until the batteries are drained and all the current has gone off to heat. To prevent this from occurring, you can put diodes in series with each battery string such that they only deliver current to the load. The down side is there is a voltage drop across the diodes. (0.6 volts for standard silicon diodes, less for power Schottky diodes.)
As for the ignitors, these are required to be heated to a temperature that will eventually ignite the coating on the wire. With three in parallel I am not surprised at the outcome. To compare apples to apples, take 8 AA cells and compare to the kit battery which is 6 cells and anyone can see that the current density/cell is going to be much higher.

BTW, I asked the question about the change pocket above because I know of several people who have done that and suffered minor burns from the heat generated by the battery and change shorting out.