Backup SQL DataBase to C$
Technically you can do it directly to \\NetworkLocation\C$ like your boss wants, but the c$ share is one of the windows Adminstrative Shares ( http://en.wikipedia.org/wiki/Administrative_share ) and is only available to users in the Admistrators group. So to use it in this case you'd need to add the user account running your SQL Agent to the Administrators group on NetworkLocation

Using these shares like this is a really bad idea. It would be much better for example to share c:\Backups\ as \\NetworkLocation\Backups$  (the $ here indicates a hidden share, so it doesn't show up in the list when a user looks at the machine). As it's not an administrative share you can set the permissions however you want for any account, without giving them Administrator on NetworkLocation

The files are in exactly the same place and you've not compromised your security so all is good.