Maybe Flock gets bought by another company and "oops, the terms changed". Maybe all contract renewals will have commercial use in the language.
Once the cameras are there, the heavy lifting (from Flock's side) has been done.
In California, it's thought that only 9% of data brokers are compliant with state laws requiring transparency and deletion of personal data.[0] It only goes down from there; most states do not have strong consumer privacy laws.
Furthermore, most municipal entities are not in a position to litigate a case over these changes for an extended period of time, and Flock is changing their terms to make it harder to terminate contracts. They can also now keep the data as long as they'd like. [1]
This, along with general corporate conduct these days, makes it very likely that they're actively planning to sell the data and might be doing so already in.
[0] https://news.stanford.edu/stories/2026/08/companies-buy-sell...
[1] https://www.aclu.org/news/privacy-technology/tracking-alpr-c...