Do we live in different realities? I've gone to lots of football games of lots of kinds of football and I've never negotiated the terms with the venue. I can't even remember bringing my lawyer!
Your negotiation occurs by you deciding to buy or not to buy a ticket. You can go to a baseball game instead. Or go skiing. There is no power imbalance. Compare government-mandated car insurance, or water/sewage service to your home, situations where one does not have great choice in providers nor can one easily walk away.
Maybe it wasn't clear, but I'm using "contract of adhesion" and "negotiation" in their customary legal meanings. A negotiation here would be communication between the parties in order to decide on the terms of the contract. Since this doesn't occur (the venue has already written the contract and only offers it as-is) the contract is deemed to be one of "adhesion". (Definitions vary among jurisdictions, and I'm only familiar with some English speaking common law ones.)
Certainly in the US there doesn't need to be a negotiation for a contract of adhesion to be binding. Not sure where you got that from - I'd be really interested a reference that says that. I would have thought a lack of negotiation is the defining characteristic of an adhesion contract. You take it or leave it - there is no negotiation.
A contract of adhesion is not binding in the US if it is "Unreasonably one-sided". I think you would really struggle to convince any US court that without a right to rebroadcast the ticket contract was unreasonable. https://www.investopedia.com/terms/a/adhesion-contract.asp
> I think you would really struggle to convince any US court that without a right to rebroadcast the ticket contract was unreasonable.
I don't know about that. Suppose something happens at the game that reflects poorly on the organizers. Could they then demand that all the fans who caught it on their phones are not allowed to distribute it? That seems about as reasonable as sticking a contract on the purchase of any other product that prohibits the customer from criticizing the product, i.e. not reasonable at all.
You're also stating it backwards. It isn't that the ticket is failing to grant you a right to "rebroadcast" the game, it's that it's trying to take away your default right to relay things you've seen with your own eyes. Notice that it's the presence rather than the absence of a term which is causing the issue.
> Certainly in the US there doesn't need to be a negotiation for a contract of adhesion to be binding. Not sure where you got that from...
Not sure where you got that from! The original question was about the legality of reporting the facts of an ongoing game by a spectator. I don't think that contracts of adhesion are in general unenforceable, but only that they are not so obviously enforceable as standard contracts or copyright law.
In fact I agree with everything you've said, except to say that I can imagine an unreasonable clause in a contract that prevents you from describing what you'd seen. I guess it would depend on the particulars though.