A sham? Unless you argue that most people are buying property under false pretenses, especially given the public nature of property taxes, the expectation would be that those purchasing land do so understanding the existence of on-going financial duties. <- There is no meaningful alternative to being scammed, the government has a monopoly on said sham, (taxation) and violence to enforce it.

You're right, everyone knows it's a sham, that doesn't make it NOT a sham.