I agree with @merzbrashed that GMPs ensure that production of a good quality product and create credibility for a company. At first glance, it might seem burdensome and costly for manufacturers to follow GMP practices, but I think it does provide a way to produce a quality product. As @mjf34 mentions, GMP is something a customer looks for as a type of mark of a quality product like a CE mark. Overall, I think GMP is the best way to go because it is beneficial to the company to produce a quality product and even if it might be costlier upfront, it’s better than producing a bad product which could end up being extremely costly to the company in the long run (unsafe, defects, etc).