https://www.mlb.com/redsox/ballpark/information/code-of-conduct"The Fenway Park Code of Conduct
Avoid balls in play
Never trespass onto the field
Drink responsibly
Help keep Fenway Park clean
Refrain from offensive language and hate speech
Be respectful of others
Keep cell phone conversations private
Sit only in your seats
Do not use tobacco in Fenway Park
Violators are subject to ejection and other penalties including a lifetime ban.If someone is detracting from your enjoyment of the game, please call the security hotline at 617-226-6411, which is printed on the back of your ticket, or text the word "security" to 23215 with message. On behalf of the Red Sox and the fans of Red Sox Nation, we thank you for observing the Code of Conduct."
This is the fan code of conduct at Fenway. Every park has one, and supposedly a league-wide policy with minimum standards was initiated last season (though I could not locate it on MLB's crappy website). Bottom line: people need to understand what terms they are agreeing to when they make a purchase.