I wonder what obligations the Swiss lords have been neglecting. Perhaps the townsfolk could bill for absent services? They are not peasants, as such things likely don't exist in modern Italy. So how can they owe anything? The Swiss baron's descendants - are they still barons? Can they still hold a fief? Perhaps the Swiss baron's lord can be convinced to levy a similar tax on them, and return the money to the town. It…
Why do you assume taxes are a payment for services? In most cases there is no written contract with rights and obligations of each party and there is no implied right or obligation of any sort.
Because the only alternative in this case is the outright theft.
>"there is no implied right or obligation of any sort."
Sorry but there is implied obligation. I totally expect to get some services in return for money taken from me and I suspect I am not alone. For experiment try sending part of government that does actual services for constituents for a year long vacation and see what happens.