Really?

Apparently Amazon have come under fire for something else lately.
They have been selling offensive T-shirts.  That is T-shirts bearing offensive messages
What I don't understand is why were these T-shirts even manufactured in the first place?  Surely if the workforce making them spoke English they would have objected, or some of them would, to making T-shirts that bore offensive messages? 
The question should also be asked, why did Amazon think it was OK to sell them, as they suggest violence against women, both ordinary violence and sexual violence.
I know sometimes you wonder about why certain things have been banned, but in this case it makes me wonder what sort of warped mind designed these T-shirts, and thought they were suitable for general sales?