To enhance our service and offer additional content to our users, advertisements will be displayed on the Cover Screen for the Weather, Color, and Daily Board themes.
I really hope that Steam games don't head down this path over time. Internet-connected refrigerators I'm willing to avoid, but that's not the only vector for this sort of thing.
EDIT: And as has been pointed out on here before, some Internet-connected cars are starting to have updates to show ads on their UIs pushed out. Any time you've already spent the money and are kind of locked in and the manufacturer has Internet connectivity to the device and can update the thing subsequent to purchase, you're kind of in a bad position regarding leverage.