Is there still tax when it's an international order? When the b&m store (or warehouse?) doesn't exist in your state in the US, that meant you pay no tax.
This is why I order from Bergdorf when I see something I like from Neimans, essentially the same company (they even share some of their online stock) but since there is no Bergdorf Goodman in CA, I do not get charged with tax even if there is a Neiman Marcus store here.
Same reason why I like Eastbay and buy from them all the time, no tax.