If each input costs OpenAI money, why does chatGPT offer continuation questions after each response?

I used the search bar function before posting this, and I couldn't find an answer (unless it's written differently than I posed it).

You often hear about people fussing about how bad AI is for the planet, and sometimes you see users on here getting on to other users for using chatGPT in "dumb" ways, thus "costing vast resources..." If this is true, why does it always want to continue the chat with questions that are usually not relevant? Is it because they want more training data right now, and do not care about the cost as of yet?