Peter Cohen, writing for iMore:
Hiding the Users directory is a little more strange. If you use your Mac exclusively and haven’t set up any additional user accounts, this may not be a big deal. But if you’re working on a shared Mac and occasionally need to access the other user directories on your computer (say, to copy files between users), this can create a real problem.
I don’t have any multiple-user-computers in my house, but I can imagine that the Users directory disappearing could be extremely irritating for those type of computer owners.
Peter’s instructions on how to unhide the Users directory are very easy to follow — your essentially one Terminal command away from getting your Users directory back.