Yes, they are paid LARPers.
* Live-action role-playing game or live-action role play: a game in which players dress as particular characters and act out their roles in the game.
* Actor: someone who pretends to be someone else while performing in a film, play, or television or radio programme.
Even if they are playing their own role in the movie/etc (maybe a documentary about themselves), it's still acting to portray it in camera, a contrived scenario in most cases.