Just starve them. The enormous expenditures on cloud infrastructure is only justified by the amount of data they harvest. Starve their data flow and their whole business model starts to crumble.
Discussion
This idea is interesting. Following the process, would less money be spent on internet infrastructure if they couldn't receive the data? It would require many to make an impact.
Perhaps costs to use the internet would rise?
I don't see why ISPs and related companies would be damaged by advertising and cloud data vampires getting dinged.
You pay your ISP for Internet and they deliver it. Whether or not Google is harvesting all of your data seems irrelevant? Maybe I'm unaware of something or missing the point though