Remember the sternly-worded copyright notice that the NFL always shows during games? That notice is a BS try-on, when compared to current US copyright law. This article explains why the notices are, in part, legal bluster.
The situation is similar to "shrink wrap" software license agreements first used in the 1980's. I remember an incident at one of my employers in 1984 when we handed our in-house lawyer the Software License Agreement that Lotus Development Corporation wanted us to sign in order to use Lotus 1-2-3, and asked him to review it. Several days later, he handed it back to my manager. He had red-lined two thirds of the clauses in the document with comments in the margins such as "try-on", "rubbish", and "unenforceable". Asked by my manager whether we should sign it anyway, his response was "go ahead. Most of the clauses will be laughed out of court if there is ever any dispute". We signed and never had any issues. (In addition to being full of legal bluster, such a contract would probably be regarded in most jurisdiction as a contract of adhesion, making it very difficult to enforce in any case.)