Folders in Windows contain files and file can exist in only one folder; unless you copy the file or create shortcuts.
Folders in EW6 collections don't contain individual items only collection containers.
Collection containers hold references to items so an item can exist in multiple containers. Items can be assigned statically (by dragging items to it) and dynamically (by using container rules).
You can create collections in each type of resource.
I don't understand the need for MyCollection and MyFolders with the availability of Profiles.