My question was inspired by this question on Writers SE. There was a debate as to whether a person could use "non-generic" song lyrics as titles (e.g. for chapters) in their own work. One person opined (in comments) "I would not use, 1) 'I Wanna Hold Your Hand,' 2) 'Ticket to Ride' in such titles.
Yet, someone other than the Beatles produced a game called "Ticket to Ride". What allowed this? Did they get permission from the Beatles? Is it that titles are not copyrightable? Is it that the Beatles never trademarked their songs?