I can't think of any good analogy for pornography.
When we are talking about pornography we are talking about sex. Issues exist about negative aspects of sex that are different to those of footballers or women working in the pharmaceutical industry. It would be nice if these issues did not exist around sex, but they do.
Women and children are not trafficked all around the world for the purpose of being made to play football. Women are not abducted, made to play football and then murdered. Being forced to play football is not a common reason for launching a police investigation. Social services and paediatricians do not spend a great deal of time looking for signs that a child has been forced to play football. You will not be accused of putting yourself at risk of crime or encouraging others to commit a crime simply because you put on a football strip. People take children to football matches all the time. In short, football exists within a completely different cultural context to pornography.
With regard to the drug analogy, it is true that there are many women (and children and men) whose labour is exploited in the production of many goods that we use. We have some options to choose products that do not involve the exploitation of women, but we cannot be sure about every single thing we buy. But we do have to eat, wear clothes and sometimes take drugs that stop us becoming seriously ill.
The other difference is that the wellbeing I receive from taking medication is because of the drug, and not directly because of the exploitation of another woman. The same is true for clothes; I enjoy being warm, not the fact a woman was exploited. If the clothes came with a video of a woman being exploited, I would have difficulty appreciating the benefits of the garment. The direct benefit from pornography is sexual enjoyment of the exploitation of another human being. That is going to have very different psychological impacts on the viewer and their perspective on people in general than the impact that using (possibly unethically produced) ventolin has on me.
Actually, I feel it is a bit absurd that I should have to justify drug use and explain why it is not the same as somebody masturbating to pornography.