I hate being the kind of internet guy who's like "X sucks" about something a lot of people have worked on, but I really, really, really dislike Finder. It fails as a file explorer on several fundamental levels. For example network shares in Finder feel so tenuous and like they could break any instant. Sometimes after you sleep your Mac and wake it up, you have to reboot to be able to reconnect to a network share.

Well, at least Finder used to be good... before OS X.

There is in fact a workaround, hold down option while copying the folder. Note that there needs to be at least one subitem in common.

that's the pretty standard behavior on unix. Unless the window manager goes out of its way to override it, mv'ing a folder to a place where one already exists will replace the old folder with the new one.

You can go out of your way to do it manually with rsync and similar tools, of course, but by default you're moving directory pointers around, not merging trees.

How many Unix graphical OS distributions are there even, let alone how many are installed?

Nautilus, the default file manager of GNOME (and by extension Debian and its children such as Ubuntu) handles recursive merge. This isn't an issue on Linux.

It's obviously bad design to have something as high level as a file manager be a glorified 2D wrapper of 2 command line tools.

> that's the pretty standard behavior on unix.

Not even slightly:

  $ mkdir 1 2
  $ touch 1/foo 1/bar 2/baz 2/quux
  $ mv -T 2 1
  mv: overwrite '1'? y
  mv: cannot move '2' to '1': Directory not empty
  $ mv --force -T 2 1
  mv: cannot move '2' to '1': Directory not empty

The window manager manages windows. It has nothing to do with the filesystem or how it's presented to the user.

They meant "window file manager", ie graphical file manager.