[JAS84]

Not sure why being a BBC show makes a difference in that regard. Plenty of Doctor Who branded merch and always has been, not to mention Strictly live tours etc.

If a licensee wants to manufacture Gladiators pencil cases or make a Gladiators video game I'm sure the rights are available for a price.

I'm not sure a video game would work well. There was an American Gladiators one in 1991 (before the UK show started, so it kept the US branding even in the UK), and well, it's generally regarded as poor. There's never been another attempt since.
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