Yes, but you are effectively turning your box into a single user system. And that's fine if you are happy to work that way, but the origins of the directory structure is of course in multiuser UNIX. As a sysadmin, I would not want my /bin /sbin exposed to everyone. In your example I question the security implications of being able to run those binaries outside of root anyway (esp. in a professional environment) if you have your box exposed on a network.
>>digita+(OP)
> As a sysadmin, I would not want my /bin /sbin exposed to everyone.
Why not? It's not like most of them are suid (right?). Most Unix systems I've used allow any user to peruse /sbin at their leisure and run whatever they want.
>>digita+1Z
Yes of course, just like on more or less any Linux system. But IIRC, shutdown is a suid binary that will do its own permission checks while running. The permissions on the /sbin/ directory should not matter.