Sadly, I suspect all celebrities - big and small - past, present and future - are targets for paparazzi. And the Internet, in particular, is a place where former child stars seem to have the worst photos imaginable posted of them in all of the where are they now and some such postings. Stars can be out of the limelight for decades, but the paparazzi manage to track them down somehow. You see links to such posts in the margins and at the bottoms of so many Web sites, even respectable ones...
As for Denise, reports about the severity of her illness and her connection to the beloved original Willie Wonka were around several days before the Radaronline site published their photos, so I can easily see a paparazzi seeking out a hospital photo shot of her on their own or possibly Radaronline even sending out a papazazzi connected to the site to get one. As I said, there's no such thing as propriety in the world of the paparazzi or sites like Radaronline...