I don't want to flaunt my experience as a Madman-style ad man in everyone's faces, but they definitely could have shot the bulk of the commercial, cut, brought in a proper ice cream, filmed a tight shot of Marky biting said ice cream, cut, taken five and refreshed Marky's parched mouth with a refreshing Gatorade, and then filmed the final line.
Indeed, and I apologise if this is too inside baseball, they could have even filmed the entire commercial with a fake icecream and then recorded the ice-cream eating scene at the end of the shoot, cutting it in to the correct place later using a non-linear editing system such as Avid, the industry standard non-linear editing system.
An example of my Madman-style ad man work as proof of my expertise:
Neighbours be Gone - Chris and Maries
