Celebrities, even e-listers like Rupert and Liberty, are probably not permitted to make exclusion lists of 5 celebrities they're allowed a free pass with... However, in reverse so the world is fair, I would like to think that every celebrity trapped in a marriage is allowed to have consequentless sex with 5 ordinary mooks just to make those mook lists less bloody meaningless.
The problem here is that two celebrities knocked boots.
Even if Kristen and Rob don't consider Rupert a celebrity, which is why she got away with adultery almost scott free.