Comment 4 for bug 16759

The way to have fancy shell behaviour enabled for new users is to put
fancy configuration files in /etc/skel. That way they go into new
users' home directories and can be modified if the user is sufficiently
sophisticated.

/etc/profile, /etc/zsh/zshrc, and other files of that ilk should almost
always be empty or non-existent. You have to remember that they're not
merely defaults: they apply to *everyone*. Don't use them.