> Which leads to the question, why is google doing this? They, you, could easily promote AMP pages while not masking the real URL!
Perhaps to allow the content to be served from a CDN (over HTTPS), without requiring the site to CNAME over their domain to Google.
If webmasters are willing to CNAME over their domain to a caching proxy, then a less intrusive design is possible[0], such as the one recently announced by Cloudflare[1].
The AMP CDN doesn't even really help with caching - when I implemented AMP at launch for some large sites, it was strongly implied that we couldn't expect any reduction in calls to our servers, and we didn't notice any reduction when AMP went live. From my perspective it appeared to be a walled garden counter-measure to FB Instant Articles and Apple News.