I think a lot of folks got this bit of nonsense about GFCIs not
working without a ground from the TV show CSI. On an early episode,
the plot revolved around someone removing the ground pin from a
portable GFCI so that a worker was electrocuted when he thought he was
protected. I remember yelling "BO-O-O-GUS" at the TV when I saw that,
and I've only watched CSI a few times since. (My wife is a fan, so I
watch it with her sometimes, keeping my comments to myself.)

I rather suspect that television shows put a moderate amount
of effort into not putting nifty new workable murder plots
on the air for the people with the play-at-home game to use...