On macOS 10.13 High Sierra, encfs 1.9.2 (homebrew) using osxfuse 3.7.1.
As user that is member of group admin: Using a mounted encfs folder works as expected - "fuse drive" is shown in sidebar, content of folder is shown,...
As non-admin user: Instead of "fuse drive", a plain document icon is shown that remains even when unmounting the encfs folder; content of encfs folder is always empty.
From shell, everything is normal.

On macOS 10.13 High Sierra, encfs 1.9.2 (homebrew) using osxfuse 3.7.1.
As user that is member of group admin: Using a mounted encfs folder works as expected - "fuse drive" is shown in sidebar, content of folder is shown,...
As non-admin user: Instead of "fuse drive", a plain document icon is shown that remains even when unmounting the encfs folder; content of encfs folder is always empty.

From shell, everything is normal.