Those refurb prices are higher than Amazon's every day price in the US.
Mostly not true:
Apple Refurb:
$679 - 64 GB WiFi
$809 - 256 GB WiFi
$979 - 512 GB WiFi
$1149 - 1 TB WiFi
$939 - 256 GB WiFi + Cellular
$1279 - 1 TB WiFi + Cellular
Amazon.com:
$674 - 64 GB WiFi (Space Gray)
$749 - 64 GB WiFi (Silver)
$899 - 256 GB WiFi
$999 - 512 GB WiFi
$1149 - 1 TB WiFi (Silver)
$1399 - 1 TB WiFi (Space Gray)
$999 - 256 GB WiFi + Cellular (Space Gray)
$1021 - 256 GB WiFi + Cellular (Silver)
$1549 - 1 TB WiFi + Cellular (Silver)
$1584 - 1 TB WiFi + Cellular (Space Gray)
The only one that's currently cheaper at Amazon is specifically the 64 GB WiFi Space Gray. The price is the same for the 1 TB WiFi Silver, and all the other ones that Apple is selling right now are currently more expensive at Amazon.
Amazon has been cheaper in the past, but we don't have that time machine handy.