Do you think this is too much for marketing films? Some shows do it, and it seems effective. However, the stunt's effectiveness could vary depending on the genre. I can't imagine a publicity stunt for romance movies.
Maybe that'll work for action and fantasy movies. You can have displays of a prop and have people wonder about it. The budget should always be considered when doing publicity stunts, though.
It's no doubt that doing a publicity stunt will catch people's attention, especially if they do it at the right time and place. I don't think those performances need to cost, so I'd say that it's worth it.
I think it depends on the project and the stunt you are planning, but overall, I'd say it's a good idea. The more eye-catching, the better in my opinion! A publicity stunt is a good way to have people remember your project.
It's okay doing publicity stunts to gain attention but be careful since some performances could cause legal issues and controversies. There's also the fact that publicity stunts won't mean automatic success for the film.