The query data they are collecting can be used for ad targeting. Remember, if you're not paying for it (and in many cases even when you are paying for it) then

The query data they are collecting can be used for ad targeting. Remember, if you're not paying for it (and in many cases even when you are paying for it) then the data collected from your use of the application is going to be used by someone to make money one way or another. Google made billions from search queries & OpenAI has an even better query/profiling perspective on its users b/c they are providing all sorts of different modalities for interaction, that data is extremely valuable, analogous to how Google search queries (along w/ data from their other products) are extremely valuable to corporate marketing departments that are willing to pay a premium for access to Google's targeting algorithms.