SD, You ignored the fact that McDonald's doesn't have to charge the same thing in both places, at this time they choose to do so.  On the federal level you are correct; Oregon doesn't receive as much for its federal tax dollar as some other states do (Look to the military industrial complex there as one of the main culprits for that.).  But that has nothing to do with this tax and I suspect you know that.  The "Oregon Tax" will become a national tax if passed, it is designed to, that is the selling point; originally, something for nothing or now, almost nothing as we continue to drill down into it.  A sales tax in Nevada has virtually no effect in Oregon.

Keep going, I'm sure you will get there and decide what is right for you.