We're a very small business based in the US. About 60% of our orders are international, with a large portion of of our customers based in the EU.
With the imminent changes in the UK and similar rules for the EU on the horizon, we probably will have to stop accepting orders from Europe. Sales (<$1K for most individual countries) simply wouldn't justify the cost and overhead of registering with authorities and collecting and paying VAT.
Shopify was and is a huge enabler for small businesses to setup shop and compete with big names. Not having to worry about credit card processing was a big factor for us to choose Shopify over other offerings.
We think that a Shopify service that collects and processes VAT on behalf of its merchants will be essential for the SMB community going forward.
We'd be more than happy to pay per-transaction fees, similar to Shopify Payments.