Why should there be a caveat of paying if you "can afford?" Plenty of people claim they can't afford to pay the equivalent of a round of drinks for content - such people don't put value on the labour of the porn performer(s) or studio they freeload from.
If a person genuinely can't afford it, which I find doubtful as they can presumably afford to run a computer and have the luxury of an internet subscription, you should challenge them to save the pennies until they can afford to pay and challenge them to look at their mindset looking at women like they're worth less than they seek for their content.
Not being able to afford porn is not a defence for downloading it illegally.
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