Possibly Definitely a targeted offer so YMMV but worth a look in your inbox.
Received an email from Google offering 20% off a Pixel phone. Email stated discount will be taken at checkout (it is).
Text of email states it's for being a loyal Nexus owner. Screenshot of email by user crv12
in comments below (thanks!). Not sure it matters, but at least one of my past Nexus phones was bought directly from Google Store.