Why do event organisers have the right to restrict the activities of photographers?

Question

Many public events such as sports, concerts, etc have restrictive policies that limit the ability of the audience to take photographs. These policies can vary from an outright ban to a ban on the use of 'professional' equipment. See also this discussion.

So my question is this: what gives the organising companies the right to enforce photographic restrictions on, what is after all, visible to a public audience?

Now I can understand their rights to make restrictions in purely private, by invitation only, events. But when any member of the public can choose to attend do the organisers still have rights to dictate the behaviour of members of the public?

Answer

You're entering into a contract - you agree to follow their rules, and they agree to let you into the concert. Any event that requires a ticket or is held on private property isn't truly a "public" event, and the property holders or event organizers can set their own rules.

It's much like this website. Yes, you may use this website for free, and it's publicly accessible, but it does have a legally binding contract that you agreed to when you made an account.

(IANAL, TINLA)

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