Hi,
This is indeed disappointing. The state of Washington has decided it is going to take a very aggressive approach to collecting sales tax on it's residents starting Jan 1 2018. I think you will start to see this from a variety of different places you might shop online in all kinds of industries.
To get around previous supreme court cases, they are now enforcing a new approach with provides two options. More or less
Option A) report sellers can collect sales tax.
Option B) they can not collect the tax, but they need to send all of the WA customer purchase data to the state of Washington so they can contact you directly to pay it. Reality is we are all supposed to pay tax on our online purchases, but almost no one does. This is how the state of WA intends on changing that. Both options are less than desirable, but of the two the state has provided there is no way we are going to select option B, even if it hurts sales. This is what we believe our customers would like us to do. However, if you feel differently we would like to hear that feedback.
It is certainly true you can shop at a vendor who doesn't collect and pay this tax for you and some of the medium sized shops are probably not complying with the new law. However, they may just have selected option B). If you don't sales tax collected at purchase and also don't want your purchase behavior sent to the state, I would contact the shop you plan on buying from and ask how they are complying with the new WA tax law. Note, if their response is "we are not compiling" know that if WA contacts them at a later date on this they will likely have the choice of either paying back taxes on all of these purchases or providing them all of the customer contact data and purchase behavior so the state can collect it on its own. Being on the government's radar is a less than desirable thing for most people...
Your state is not alone in this; others are following suit. In fact, south Dakota has a request to the supreme court to revisit the entire topic. They have indicated they are likely to do so. I think what amounts to tax free shopping on the internet is likely going to see an end in the somewhat near future. States want this revenue and they are going to find a way.
https://www.bloomberg.com/news/arti...ernet-tax-ruling-tees-issue-up-for-high-court
While probably not a very satisfying answer I hope this helps to some degree.