Im guessing they have got a good deal from Hamilton Airport, but wii pax really want to fly there if going to Toronto it self when you have a shed load of flights in to YYZ. ie AC, BA, TS, TCX, MYT, OOM from LHR, LGW, STN, EXT, BHX, MAN, GLA, EDI, NCL, CWL, BFS.
Also Hamilton is around 56 miles to central Toronto (further from the airport.) and a bit less to Niagara Falls.