Yes Public Folders are not accessible and yes it's pretty rubbish. I wanted to have a shared contacts and shared calendar for the company. I think there's a way you can set up one account and share that contacts folder or a sub folder of contacts to everyone. Even then I'm not sure that will show up on mobile devices. Doesn't necessarily need to be a whole new one but that would be the cleanest way in case the user leaves.

I'll be interested to see if there's any real solution to this.