A slight correction here, the download of the exe does take place over https. As does buying the software, and signing up to the forums. But everything else doesn't?

The software itself is some of the smoothest and most stable I've ever used. And when there's an update within the software that, as far as I'm aware, takes place over https too.

But the rest of the site and forums, even when signed in, is http, and I don't really know why.