It will be good to use those domains for redirects/PPC landing pages, etc... anything that does not involve PBN-s, money sites or something blackhat we always try to hide from Google. Of course that is if they offer competitive pricing which I am sure they will, at least in the beginning to gain more recognition. And they surely have the budget to afford losses at first lol.
I don't see why you couldn't do a PBN really. I doubt they could possiblly manually review every domain they sell.
This is how they ruled Internet. People will definitely go with google to buy domains.
Here's the ultimate bad ass challenge:
Use fake data on a google domains registration.
Rank the shit out of payday loans.
Publish the results for black hat beer, shits and giggles.
Become Alpha Male leader of the Black Hat Legion.