I guess the Apple engineers would have prepared the demo and analysed the copied ROM, before going to the court. Then, they would have found the routine (somewhere else, as you point it out) and easy to activate.
I could see a really compelling demo where they bring out the machine still in the shrinkwrapped box, open it in front of the court, turn it on, and hit the register.
I could see a really compelling demo where they bring out the machine still in the shrinkwrapped box, open it in front of the court, turn it on, and hit the register.