Um, in many states that is illegal.
https://en.wikipedia.org/wiki/Revenge_porn
That is a big fucking deal.
ETA: It doesn't fit most revenge porn laws but it is still a big deal
While I don't agree with the posting of nudes of ex's, I don't believe that falls within the realm of "Revenge Porn" since the pictures that posters submit on that site are taken by the ex's and they're given to the posters willingly. They're not used to blackmail the ex, nor are they used to coerce them into continuing the relationship.
To give you a window into the Shag, a former Louisville cheerleader once tried (unsuccessfully) to get the Shag website admins to take down sexually explicit pictures of her that she took and sent to an ex. They were taken with her consent, but obviously she didn't want them posted online. After a long, drawn out legal dispute the Shag won, and now the website admin uses her picture (cropped only, PG quality) as his avatar.
Given the above situation, I doubt there would be any legal ramifications if GB took the picture from a public profile. Even if he didn't take them from a public profile, I doubt there would be any legal ramifications unless the girl in the photos didn't know her picture was being taken. Moral implications are a different matter, but given the fact she's clothed in the pictures we're not talking about cardinal sins here.