Pricing is a potent weapon in moral purchasing. If something moral costs the same as something immoral, then people will buy only what is moral, if they know. If something moral costs more, people can deliberately pay for it and make it a status symbol - paying more for something that is morally better makes them morally better. If something moral costs less, then only an idiot would buy the immoral thing and pay more - so pointing that out can shame people and cost them status. Only if something moral costs a lot more could the immoral product actually survive.
So, how much more would the moral product or service have to cost, before the immoral one could be sold in competition with it? Let's guess, since we don't know. Let's assume that the rating for the product and another rating for various types of countries involved in producing it, are combined by adding (see talk:types of countries) to give a number from -4 to +5. If that represents 1% cost difference, then buying the "most moral" product may be worth up to 5% more for those who want it as a status symbol, and the "least moral" product may be worth up to 4% less, than one that we know nothing about. That's a big profit margin. If you could make a 3-5% difference from say -2 to +2 by making some minor changes in supply lines or production technique, that's more money than you would make than by almost any other method.
Discount and coupon and frequent buyer programs can lock in these benefits by bringing the price even lower for those who commit to a lot of buying of the moral product. Incentive programs that give you buying points when you buy certain products might be the most potent though it is not easy to pressure supermarket chains for instance NOT to offer bonus points to those who buy immoral products.
When pricing fails, picketing will probably work.