[throwaway765123]

Disclosure is technically required, but in practice I see undisclosed ads on social media all the time. If the individual instance is small enough and dissipates into the ether fast enough, there is virtually no risk of enforcement.

Similarly, the black box AI models guarantee the owners can just shrug and say it's not their fault if the model suggests Wonderbread(r) for making toast 3.2% more frequently than other breads.