Short answer: It is easier to prejudge someone beforehand rather than to put yourself in this person's shoes.
Long answer:
I see this as a scenario where some A dude/dudette would try to argue with some one about one idea/case/occurrence which is totally away from his/her reality, maybe giving little credit for whom is defending a cause (in this case, the right of abortion).
As cliché as it could sound, try to imagine, say for this example, a white rich studied average person who doesn't run into too much trouble in his/her life and has family support and so on..., only prejudging some poor woman who wants to have such right of abortion, yet the other persons knows nothings about what the life of such woman could be and still tries to complain without having real understanding of such situation, only because it is simple to judge someone rather to be on someone's shoes.