Why? Because apparently they need some more incentive to keep units occupied. Also, even though a property might be vacant, there’s still imputed rental income there. Its owner is just receiving it in the form of enjoying the unit for himself instead of receiving an actual rent check from a tenant. That imputed rent ought to be taxed like any other income.
That’s not true. If I receive artwork, a car, shares of stock, room and board, free tuition, etc., then that is income on I which I will owe taxes. Figuring out the value of these things isn’t a guess. It’s an estimate based on actual market data. It’s actually kind of easy in the case of a rental property since the landlord will have advertised the rent amount. So, if he wants to pay lower tax then he can just lower his ask.