Lego customer support was quick:
Hi Michael,
Thanks for reaching out to us, we're always happy to help.
We're so sorry our website is applying the shipping charges, thanks so much for letting us know about this issue!
We'll be working hard on our end to fix this but in the mean time we've removed the shipping fees manually for you. :)
Also if you still need it, your order number is T37xxxxxxx.
Thanks again for letting us know about this issue and if you have any more questions about your order please let us know.
Have a bricktastic day! :)