Eureka's Transaction and Use Tax

I've been doing an e-mail exchange with a local in- the- know guy about Eureka's Measure O- the Transaction and Use Tax- passed a while back. I was unaware that this tax can be applied outside of Eureka:

"The tax is levied based on your zip code so if you make a major purchase outside of Eureka, and yes anywhere in the state, and you report your zip code then the entity will levy the additional tax.  For those who are in the unincorporated areas of the affected zip code there is an exemption provided."

That reads to me as if you buy a refrigerator in Santa Rosa, they charge the half cent sales tax, too. How they would keep track of it and send the money back to Eureka, I have no idea. Or maybe I'm not understanding this correctly.

Either way, sounds like a smaller version of what some states have been trying to do lately in getting other states to charge their sales tax to people of one state that make purchases in another. Anything like that should be illegal.

More info from the Board of Equalization here.