Compared to every other club it makes no sense. .
It is just that they are the only Victoria based club that still have their original home ground to enjoy that advantage that you noticing it more. Most other Vic based clubs virtually have no home ground anymore. My club certainly don't since we left our true home ground at Princes Park.
It is regular home ground advantage if you look up raw stats of leading ones below:
Collingwood at Victoria Park historically won 74.8% of games at home.
West Coast 76.5% at Perth Stadium.
Carlton 70.7% at Princes Park
Adelaide 69.2% at Adelaide Oval.
Essendon 67.3% at Windy Hill.
Geelong 67.1% at Kardinia Park.