Television cameras captured Cairney behind the dugout during the match, which he is understood to have attended in a personal capacity alongside former Fulham team-mate and close friend Matt Smith, who is now at QPR.
However the Hammers boss insisted Cairney's close proximity was nothing more than coincidence.
Asked about Cairney, Moyes said: “No idea, was he?
“If he was then it certainly wasn't a ticket from us. I was hoping you were going to say Lionel Messi was sitting behind us!"