These are probably a result of some arcane law that fenders must be fitted to all bikes, with the law not specifying the length, so shorty fenders met the legal requirement if not to actual intent of the law. Sort of like being stopped by the cops for no bell on a bike, only to respond that the law requires "audible warning of approach" so if you can shout "get out of the way" then you are in compliance. I got away with that several times in the UK.
Brian Booth
Toronto, Ontario, Canada