Maybe your friend is thinking too much about enterprise set ups. I have no need for sshfs at work, but for my personal servers that's a different matter. I find it invaluable to have the convenience of being able to have an NFS-like share over a simple and secure SSH socket. Yes you could literally run NFS over VPN or an SSH tunnel, but sshfs is just so much more convenient.

So really it just depends on what you're trying to do as to the practicality of sshfs. But then I guess you could argue that is the case for nearly all the commands that many sysadmins have flamewars over.