In a MLB game televised a few weeks ago (Cubs and somebody), the announcers went on and on about how PU Mike Winters was/is supposedly 'known' for favoring the home-team pitcher with his strike zone. Every time this F1 got a close pitch they cackled, 'see? there he goes again.'
I don't think umpire-bias tales are unique to any level or regular/replacement umpires.