While I believe the whole thing is a fumbling attempt to get money and that the perpetrators are lucky they are getting sued or worse (Based on HTTR24_7 and others twitter feeds about this), the "Why would he do it?" argument is perhaps not the most persuasive.
Tiger Woods comes to mind. And of course,
Your married to her:
Yet you pay to have sex with her:
Rich men and sex ... just 'cause they can.