Canada. I used to order a lot of stuff from Europe and hadn't had anything similar. You'd think they'd want to promote trade between the U.S and Canada by having low custom fees.
What's worse? It's 100% subjective and arbitrary. Had the same ~$40 customs charge on my first Pax. Returned it, ordered a second expecting to pay again and then BAM: clears customs in minutes without any fee at all. Cash grab indeed; good things the Pax is worth it
EDIT: Noticed the discussion moved on to "fuck UPS". Just thought I'd throw it out there that I specifically requested USPS (Ploom was happy to oblige) as I'd heard they have frequently lower fees. Sort of a toss up here: unit #1 I had same as Onion, second unit I had $0. So confusing.