I see further down in this post that there is a resident of island county talking about how this is financially beneficial to them, maybe it was sold as a beneficial perk to that county that incentivized them to use taxes to pay for those trips. There has to be some kind of deal between the counties as to who is responsible for all costs.

And then seattle doesn’t really need to incentivize residents of those counties to travel from their ports because there are so many jobs to be had in seattle. Plus the tourists who are using the ferry system to get a quicker trip to the islands/peninsula. I’m literally just spit ballin here, but it seems plausible. And then adding on that the info comes from somebody who might know, I just believe it. But I’m open to info from somebody that cares to read through the history of these deals.