One of many examples: read "Out of Poverty" by development economist William Easterly. Think about an individual in a third-world country with the following alternatives: sweatshop, Crime, Nothing. While this set is contrived it is not an inaccurate description of reality for many. It is easy for those in rich countries to lose touch with how difficult those in undeveloped countries have it, Or to make lazy, Feel-good arguments which come at the expense of those they claim to help.
ARGUMENT: Sweatshops are not necessary. It is more important for people in poor countries to have human rights than for people in rich countries to have cheap clothes.
EXAMPLE: For example, sweatshop workers do not get paid enough money to live on and miss out on many human rights, including the "right to a fair wage".
CONCLUSION: Sweatshops do more harm than good. Sweatshop bosses are too greedy. There are better factories to work in.