There are several fun monster movies where people try everything they can think of to stop or kill a monster, but nothing works, so they try gas to knock it out, and it works, like King Kong, for example. So I thought it might make a fun ad to show a scene from a movie like this where gas is used to stop a rampaging monster, and the announcer says: “Sometimes, having gas can be a good thing.” Then we see someone sitting in a crowded movie theater, and we hear a loud gas-related intestinal gurgle, and the announcer says: “And at other times, having gas can be a bad thing. To stop gas when it’s a bad thing, use Gas-X.”
And maybe the person with gas is in the theater watching the same movie referenced.