Many years ago I met a car salesman who on starting with a new company asked to be allowed to deal with any customers that had complained about poor service. He eventually became the top salesman and earned the biggest commissions!
The moral here is that when complaints can be turned into positives it often results in loyalty and recommendations.
Owning my own retail businesses for the past forty years I always made an attempt to speak personally to any customer who felt they needed to complain either about quality or service ( and that in a company employing over 400 staff. )
Getting back to the original post...maybe it would have been more productive if the op had contacted the owner personally and then perhaps Greg wouldn't,t have felt the need to bounce back with his defensive response.