MichaelJP59
Perhaps the pilot should do a quick stick-forward "bunt" at the top of climb to demonstrate what could happen
Note sure that Cabin Crew and the legal department would appreciate that kind of stunt.
This being said, there must be a way to show people what happens in negative gravity. Maybe some videos shot in a vomit Comet/Airbus could do the trick, especially if you show them in the middle of those cr@ppy amateur videos of kids falling from their bikes or dogs bumping into the camera