Thanks for providing that discussion link. I had no idea there was a SW switchover of carriers at some point & all that history. I know all about the UPS/courier headaches into Canada. A buddy of mine who also imports a lot of personal hobby items wrote a step by step procedure of how to self-claim & mitigate all but 5$ dinger fees inflicted by couriers. It turns out you are not even obligated to pay UPS these fees but of course they will never tell you this. But the procedure is a minefield of responding to the delivery notice in a specific way, completing specific declaration forms & generally involves a visit to a UPS facility. On an expensive item maybe worth the effort. On a less expensive thing its a PITA which is exactly what they are counting on. Its an irritating racket to be sure.
And yet, similar to the China analogy, I can order something from Amazon.com (yes dot com not dot ca) & it arrives to my door lickety split in a UPS box, no extra fees, no nothing, generally free or inexpensive with Prime. It all depends on the deal the vendor has negotiated with the carrier. Amazon is a gorilla & I don't suspect many others have this clout.
This problem is exactly why there is a booming business in specialty shops in Canada now that fill this need. When you order something, you specify their USA border address as the shipping location & they take it from there via bi-daily trucking for a fee, but is much more reasonable. There may be a stipulation that value is <800$ or whatever the current goofy limit is & minimal customs paperwork which says made in USA which it would be & be duty free.
So my recommendation to Shapeways for non-USA customers is to allow a shipping address that may be different than the home/billing address. Maybe this is already the case, I'm not sure? Amazon has had this provision for years. Then it can go from print facility to USA address (probably very reasonably via UPS as USA customers enjoy) & we use a non USPS / courier / Canada Post to get it home.