I don't think it's been explicitly mentioned yet, but a morals clause in someone's employment contract is not the same as a no-fraternization policy. They are different things. As others have already mentioned, there is a big difference between a consensual relationship between co-workers and sexual harassment/coercion.
Consensual relationships can lead to termination or action, of course. Jed Bernstein was forced to resign as president of Lincoln Center several years ago over a consensual, but undisclosed, sexual relationship with a woman who reported to him. Most companies require employees who are in a relationship to disclose that fact so that there isn't even the suggestion of impropriety.
On the other side of the coin -- for most people, whether they work on Broadway or in an office building, work is where they spend the majority of their time. To say that there can be no dating among co-workers is unfair and unrealistic.
"You travel alone because other people are only there to remind you how much that hook hurts that we all bit down on. Wait for that one day we can bite free and get back out there in space where we belong, sail back over water, over skies, into space, the hook finally out of our mouths and we wander back out there in space spawning to other planets never to return hurrah to earth and we'll look back and can't even see these lives here anymore. Only the taste of blood to remind us we ever existed. The earth is small. We're gone. We're dead. We're safe."
-John Guare, Landscape of the Body