How much each team flies vs. busses to games varies quite a bit. Some teams fly a lot, and some rarely do. Even in the NHL, NFL, MLB teams will still use busses or trains for nearby opponents. NYC teams obviously don't fly to play each other, and even for games vs Philadelphia they usually don't. Getting 30-40 players, staff, and equipment to the airport, through security, on the plane, off the plan to a bus, traveling from the airport to the arena, unloading again, etc. ends up eating up any time savings from the flight.
A quick google search indicates Belleville does not have a commercial airport. It is 122 miles from Belleville to Toronto's airport, so teams coming from a distance would likely fly there and then bus to Belleville. I would think Laval, Syracuse, Rochester, Binghamton, Providence, Hershey, Lehigh Valley, WBS, Bridgeport, Hartford, etc would all bus there even if there was an airport in Belleville.