I'm a little mystified by this choice. It helps a bit with the long haul between Burlington and Centralia, which might be too far if you get stuck in city traffic, but it's still too far from Arlington to make it to Ellensburg.
I'm guessing the casino must have made a very sweet offer, hoping to get a few Tesla drivers inside the door while they wait.
It also may help with the increasing crowding at Burlington, but I think Centralia and Ellensburg are both much more pressing on that score.
Maybe they've noticed that Washington state is far behind anywhere else with a comparable population of Teslas.
Although I think this was a poor prioritization, if the casino is the answer, it's promising for what's to come: more and more places will realize having a high speed charger in their parking lot is good for business and costs them very little in comparison to the business it can bring. If you're listening, Tesla, think about Emerald Queen, in Tacoma or the new one in La Center (near Longview)
(For some reason, I've needed to stop at the rest area at 7 feathers just south of Roseburg, OR, every single time I've been through there.
-Snortybartfast