"I think it is about whether or not the sex life of a public figure affects their ability to do their job, an actor? No. Politician? Yes."
No I don't think it is just about that. As others have said, the actor/ pop singer/ footballer etc., is not just doing their job, they are also getting other jobs - lucrative advertising deals, marketing campaigns, merchandisng etc., off the back of their public image.
Their public image is part of their money making. There is something pretty revolting about a man like Wayne Rooney who is married with a child, using prostitutes. So he is not the best man to front a coca cola campaign because whenever I look at him, I think what a skank he is (not consciously, but sub-consciously). That also affects my perception of the brand he is selling. Brand Rooney depends on certain core values being synergystic with Brand Coca Cola, Brand Nike, Brand Walkers Crisps etc. (I know he doesn't advertaise those, but I think another shagger does? - can't remember which one). If the brands of the foootballers/ actors, etc. are tarnished too much, the brands who look for celebrity endorsement to sell more of their product, will not want to work with them, because they will be bringing their product into the saem company as the sort of skankiness associated with the England football team, for example. And that skankiness rubs off on their brand. It's the reason premium brands won't advertise in certain low grade publications or TV programmes - it's not jsut that they want to target their audience efficiently, it's also that "the company you keep" as a brand, re-inforces your brand image and you undermine it by putting it in the wrong place or associating it with the wrong person.
And whoever said it's not a judge's job to protect the brand image of a person or corporation, is right. It is a disgraceful misuse of the law IMO.