They are part of the Room Booking Module, the newest feature the company has added to its Google Hotel Ads product.
In your current Google Hotel Ads campaigns (which Google calls Standard), you can choose whether you want to redirect the user to your website or to the Book on Google funnel so they can finish their booking there. It is your decision to activate it or not.
On the other hand, in campaigns which are part of Room Booking Module, all users will be redirected to Book on Google, without the possibility of redirecting them to your hotel’s website. We understand that this move by Google is to boost Book on Google and looks increasingly strategic.
As of today, RBM results are not shown on standard Google searches of a hotel name on a desktop computer. However, funnily enough, they appear on searches from a mobile device. On a mobile device, in the Overview and Prices tabs, you can see the RBM room photos.
Get the full story at Mirai