We routinely buy tickets that incorporate an ethereal set of “terms and conditions” that are too numerous and lengthy to print on a small piece of paper. When part of a commercial transaction, courts often enforce arbitration requirements in those bonus provisions. Trying to extend that robust body of precedent to a situation where nothing was sold, the Chicago Cubs argued that Charles Arbogast — an Associated Press photographer who alleged he was injured by the club’s negligence while covering a game at Wrigley Field …