Maersk had the same thing at BHX and actually had a route pulled from them when it became too profitable - BHXFCO
Maersk didn't ever operate BHX-FCO, it was BA then BA Regional until it was dropped. And if it was so profitable why on earth has no one else picked it up apart from (briefly) WW?
As for GB from MAN I can actually believe BA stopped certain routes from happening to protect feed on the Shuttles