[tzs]

Would you object to a bookstore that tests playing low volume classical music to see how it affects sales?

If it increases sales and so they keep playing it, is that manipulating customers and unethical?

What if the reason it increases sales is that it makes the customers find the bookstore more pleasant and relaxing, and so it makes the customers happy to spend more time there, which results in them being more likely to find a book they want to buy?