Because how you're taxed is ultimately arbitrary and the concept that you should only be taxed once per dollar you earn is an idea you made up in your head that has no bearing on reality.
Or as a more amicable answer, property tax is municipal, sales tax is provincial, and income tax is federal (at least where I live).
I understand property tax in the US mostly finances public service, such as schools and libraries, so maybe you want to pay not to live in an area full of ignorant analphabetists which would seriously impact property values.
Or as a more amicable answer, property tax is municipal, sales tax is provincial, and income tax is federal (at least where I live).