I thought they changed it.
They extended the Chrome app so that you can configure the Trezor without sending any data to Satoshi Labs (or anyone). However, myTREZOR (or the wallet of your choice) still needs to know which addresses have been used in order to determine your balance and history.
Yes but there is a choice - the Trezor finds the addresses on demand and send to server via the web-page, or the webpage, knowing the XPUB, sends the addresses to the server, or the server gets the XPUB. Three possibilities. I looked over the bitcointrezor.com site in hope of finding the answer, but I didn't. So you are probably right, the XPUB is sent from the Trezor all the way to the server.