I think they’re very cautious to make their public appearance only in a work context even if we know they do see each other outside of it. They know we and the press would go crazy if they were spotted having a meal together for example. It would undoubtedly lead to all kind of rumors and they want a total control over that.
It just means that if you want to not be seen, you can do it and they’ve both mastered this art in the last few years.