I'll make you famous (or Adidas will)

Because even though its shit, its better than subsistence farming where you work night noon and morning to keep yourself barely alive. If you're working in a factory/sweatshop, you get to meet people your own age, experience a bit more excitement with city life, have a few quid to do a small bit of socialising. People will put up (to a certain degree) with the mind crushing labour and horrible conditions because its preferable to bending over picking through the earth for the rest of your life.

Obviously neither situation should exist in that people in poorer countries should get fairer compensation for their work.
Nicely stated.