You've heard of the Barbara Streisend (sp!) effect right?
Suing would have kept the story in the papers for even longer - instead by keeping a dignified silence on the issue the only fame Loos has is that a few people on the internet are discussing how she once did something with a pig - and if it wasn't for Sharon Osbourne would we even be doing that?
But they didn't keep a dignified silence - nothing like it.
They just went off on a skiing holiday, draped themselves all over each other pretending everything was fine while the paps stood by and took pictures.