I agree with elmstedt’s interpretation that this is against OpenAI’s policies, the usage policy also has the following text:
Don’t use plugins to automate conversations with real people, whether by simulating a human-like response or by replying with pre-programmed messages. (Same link as @anon22939549)
Ads are not allowed in this context as they fall under the “replying with pre-programmed messages” part.
I don’t think there’s a need for an “official OpenAI response” on this question, it’s already very clear that this isn’t allowed.
Keep in mind that the law and contacts that you sign, are ment to set the bare minimum of expectations, it’s not the gold standard of good behaviour. 