This is the problem that we see again and again and again with libertarianism - it ignores the human element entirely. It assumes most people to be rational, intelligent, and moral and ignores mountains evidence to the contrary. It's like the honor system for politics. You also ignore the fact that nobody with a full time job and a family to take care of has time to sit around searching obscure alternative news sites for the hundreds of products in their homes. Not to mention the frequently-encountered issue of a needed item being made by two or three companies who all commit the same sorts of abuses. Who do you buy from then? How many families do you seriously think sit down and try to tackle these issues?
So, Because some people fail to be responsible, I should support you stealing from everyone else to force them to be?
People offload decision-making all the time. The government isn't fixing that. If it was, It would ban Coke from US shelves because of the labor disputes. What I suggest is that we stop stealing from people, and let them choose which decisions to offload. Private ratings companies could do all that tedious research, and that poor, overworked mom could only buy products marked by the ratings agency that they trust.