I don’t know about the UK, but in the USA the idea of “if you don’t want to be in photos published online, don’t be in public spaces” is pretty regularly upheld in courts. You don’t have an expectation of privacy in a public space.
You might have some recourse if another person’s video singles you out, but just being one of the several people in an airsoft video, where your face is partially obscured anyway, isn’t much of a legal standing.
Yea, and in this case unless the property owner says no filming said person would have no legs to stand on.
In most 'fun' events like this with random members of the public said venue has a monetary interest in ensuring people can film in the vast majority of the cases. People go there to have fun, and sharing videos of said fun is but one more way to ensure they get future customers.
You might have some recourse if another person’s video singles you out, but just being one of the several people in an airsoft video, where your face is partially obscured anyway, isn’t much of a legal standing.