A website owned by someone in California shows an offer to a man in Illinois from a company based in Chicago. The deal is concluded between Illinois and Chicago, the website owner is not involved in buying/selling whatsoever.
It will be an even greater mess when/if Illinois starts to charge tax and lays claim to a portion of the sale. Let alone cities such as Chicago. Governments are feeling the pressure of the economy magnified by unrestrained spending. Instead of looking for good ways to cut costs we can expect tax hikes.