I think you comment points to two current underlying real problems in how we pay for government. paying for state government now depends on consumption (sales tax) and state and local governments are highly dependent on the price of real property to constantly rise. I suspect sales tax rates above 9% is inelastic (which basically means you can continue to raise the rate, but gross receipts is stagnant or fall).
Interesting, hadn't thought about it but now I agree that sales tax rates above 9% are probably inelastic IF people can buy elsewhere. California sales tax on cell phones is horrible, somewhere in the 20% range. I now make sure to buy everything from Ohio (where I live, so it's legal, but I am in California a lot). However, if I lived in California, I'd be stuck with it. So the elasticity of sales tax is a function of place and the underlying product...and maybe some other stuff.
My county government gets almost 38% of its general fund revenue from sales tax, and something like 75% of its sales tax came from car sales, before the recession. Now I understand why the lights are timed to make me stop in front of those stupid dealerships. When car sales died, so did the county's revenue. Of course, property taxes are also a big source of revenues. So if property values go down, governments have to make up the difference by raising rates (or perhaps mills?).