Since Chromebooks are very internet-forward, they get plenty of advertising opportunities without installing banner ads or something similar into the OS. Are you expecting them to start advertising on the Android home screen too?
They already do something better for their ad business moat. They just push their Google Apps bloatware collection on the Android ecosystem at every possible chance they get. I use none of it, yet it still comes with my Samsung phone whether I like it or not. I would expect them to continue that approach with any operating systems they control.
Seems counterintuitive that you take such a strong stance against bloatware and yet use a Samsung phone. The preinstalled (and non-removable) mountain of crap was the reason I gave up on them after my Galaxy S3.
Not that other vendors are much better, mind. But I'm quite happy with my OnePlus for now.
