blind bandwagon

A person that only likes a sports team because...
•it has their favorite player
•their friend(s) like that team
•they no nothing about the sport
•etc

J. That guy is terrible at football
H. I know
J. He doesn't know any of the rules or how to play
H. He only knows knows the Patriots because he is in love with Tom Brady's wife
J. He is such a BLIND BANDWAGON