Google Pay doesn't seem to work in quite the same way as Apple Pay.
On the phone it's the same, with tokenised PANs (DPAN).
On the web, it does work differently. Because you add the card to Google Wallet first and then 'verify' on the device, the original card PAN is held by Google. So on devices where you don't have the tokenised PAN in a secure enclave (eg. your laptop) they use the card PAN, like any other online transaction.
Although this is rather moot as the industry is moving to merchant tokenisation anyway (MDES for Merchants, in Mastercard land).
Whenever i use either physical card or Google Pay on Plymouth Citybus, it still logs all journeys under the same card number regardless of whether the card or phone is used.
There's an API which allows certain merchants to do a 'reverse lookup' of DPAN to PAN to enable them to show this journey history across all devices linked to the original card. It used to be limited to TfL, but it now seems to be available more widely to those doing transit things.