The crowd at MetLife Stadium was pretty "mean" to Taylor Swift during Monday Night Football ... with New York Giants supporters booing the hell out of an ad for the NFL's newest super fan amid her budding relationship with Travis Kelce.
Swift's presence at the past two Kansas City Chiefs games has been the biggest story in football ... and the league has leaned heavily into the craze, even using her name and image across its social media platforms.
Giants fans made it clear they were fed up with the Tayvis hype during the primetime matchup .