Daniel,

Lets add age to the analysis:

• the PDF of two friends seeing Kung Fu Panda 3 together is skewed to the left (lets say, a tendency to early teens or below)

• the PDF of knowing how to perform the lengthy part of the analysis is considerably skewed to the right (lets say, a tendency to late teens or above)

• it is actually here that the analysis becomes slightly more complicated:

  • in comparison to the above, the PDF of knowing how to use Wolfram|Alpha or the Cloud to just call for Probability[...] (the quick part of the analysis) has its first moment more to the left, and a higher second moment, which is kind of risky, but, at the same time, can be done while inside the taxi, or even walking to the cinema... (Siri can eventually help them on this...)

  • if they are indeed on their late teens or above, the geek sharing tendency probability has to be accounted for. They will probably wait to be together to try the lengthy part. They will not see the film while trying to do the analysis on the Cloud. But if you paid attention, the above analysis is focused on getting inside the cinema together. Not on the looking at the film aspect.

• another important clue is the fact that neither of them are using their own car, and, although not explicit, it does look like they are going alone to the cinema. This can eventually be added to the analysis. But to do it properly, we would need to know a little more about the city typology. We can notice the use of the words "downtown" and "suburb", but I'm not sure if this is enough to categorize the car->age or the security->age distribution.

you see where this is going... they are probably on the safe side of your concern...

PS - by the way Shenghui Yang, +1