I wouldn’t say Jackson or Josephine county “want” to join Idaho. There has not really been political talk or any votes for such a thing. The counties that want to join Idaho are east of Jackson county and have much smaller population. Anecdotally, everyone I know in both counties are proud Oregonians and would never vote for such a thing, even if they do hate Portland. The anti-tax sentiment is a separate issue all together.
In Oregon tipped employees are required to be paid the state minimum wage. Tips are considered extra on top of that. Seems to be an exception though unfortunately.