For many many years people could walk the beach nude, and some of the establishments even welcomed them. I've had very pleasant meals at Andy & Cheryl's, Le Pirate and Kontiki for example all sans clothing. But as that section became more popular some of the less welcoming establishments started to complain and a crack-down was implemented.

I don't know if nudity is technically legal anywhere on St. Martin, but it used to be tolerated (even welcomed) the length of Orient beach. It's unfortunately that the whole beach isn't as welcoming to all comers as the Club O end has always been.