How do I remove a shared folder in Dropbox without deleting the folder

I love dropbox, yet I hate the fact that I can only get a a few GB for a free account and yet my friends find it a good way to share photos. (Indeed, photo really take up lots of space and we really need a web service to tackle that problem alone.) Sometimes, my friends just put too much photos on dropbox which exceed the limit of my account. What I can do is to remove that folder, yet I heard about an incident that someone in a shared folder accidentally delete the folder instead of just removing it on her own account. So I dig up the Q&A in dropbox and found the link below, which teach how to "leave" a shared folder, meaning the content of that folder will no longer count towards your storage limit.

How do I leave a shared folder? - Dropbox