they have different faces...
maybe the user is selling out private photos/videos of somebody who doesn't even know they've been filmed?
Or maybe he has some other like celebrities that aren't available on the web for free?
Or he is just a pornography lover and collecting nude pics over the internet.
Of course, now he had just had the idea to make money from his passion. So, the business idea of OP is selling nude pics online to people who's does not have internet access and he can't find porn pics.
Or I am missing something?
btw. OP do you have permission to resell these pics, I guess they are not yours personally?