Occasionally CSS and font files served from www.etsy.com via Fastly (and only Fastly) are not gzipped. None of our other CDNs appear to have this issue.
We have seen this effect via Zoompf alerts, Catchpoint tests, and can reproduce it with curl (again, intermittently):
curl -k -H "Host: www.etsy.com" -H "Accept-Encoding:gzip" -v "https://global-ssl.fastly.net/assets/dist/css/base.20141024160711.edge.css" -v > /dev/null
Compare to origin:
curl -k -H "Host: www.etsy.com" -H "Accept-Encoding:gzip" -v "https://origin-www.etsy.com/assets/dist/css/base.20141024160711.edge.css" -v > /dev/null