The chatbot sidebar seems to also be the only way of accessing certain Amazon features, like the price history. And it seems to be implemented in a particularly silly way - clicking the "price history" button prompts the chatbot to show you the price history, rather than just showing it.

I think the forced-chat price history thing is a dirty way of trying to get people used to talking to the chatbot. Can't think of any other reason it would be designed so stupidly