A good point, but realistically they've calculated the impact of going after even a handful of Dick and Susie users doing it, and recognized it's not worth the fallout it would generate. They're pretty tied up going after the content creators and uploaders at the moment.
Additionally, it would reveal more about how much data Google has access to, and its capability to use it in ways that are generally seen as intrusive.
If they wanted to play a card, going after the software distributors and a handful of software developers would be more likely to influence the desired outcome.