Incentives > moral shaming
Discussion
Doing business with a calibrated moral compass doesn’t harm the business, in fact in a free market it actually helps.
If this were true, then the most moral businesses would dominate the markets. But we don’t live in a free market so I guess you can’t really prove that.
Every exchange where both the buyer and the seller are happy with the outcome is an example of moral business practice. You are right that today we don’t have free markets, but fortunately not every business owner is a crook, so we have enough examples even today. Customers that are happy with the exchange will prefer to work with the business that provides more value for their money, unless coerced is some way.