When comparing a sales chatbot agent with a sales human agent, there is no difference. A chatbot answer would be no more legally binding than a human's answer.
The actual reduction in liability would come down to who can make less mistakes, the fact that the mistakes are or aren't legally binding does not change the decision to put a chatbot.
In fact I think you are plain wrong, it's standard case law that errors in pricing are not binding, if you find a wheel of 50kg cheese priced at 30$ (the price of a kg of cheese), then the supermarket is not obligated to honour that price, they obviously mispriced the cheese.
The actual reduction in liability would come down to who can make less mistakes, the fact that the mistakes are or aren't legally binding does not change the decision to put a chatbot.
In fact I think you are plain wrong, it's standard case law that errors in pricing are not binding, if you find a wheel of 50kg cheese priced at 30$ (the price of a kg of cheese), then the supermarket is not obligated to honour that price, they obviously mispriced the cheese.