[SuperSajuuk]

Why do shows like Gladiators, Pointless and The Chase get “celebrity specials”? It was the same when The Crystal Maze got rebooted by Channel 4

Celebrity specials can be packaged and sold on as standalone episodes, because they have no returning contestants so there's no narrative. If you wanted to sell something abroad but your audience in another country (or the broadcaster in another country) may not want a full-length civilian series, celebrity episodes are a good thing to have for the broadcaster as a "taster".

I don't have issues with celebrity specials personally, they're a bit of a laugh at the people who get picked that often struggle with relatively basic things that most others can do easily.