That's the way I understand it.
By default the guest account is set to nobody, so if the guest account is not in the file or commented out, then that will be the account that gets used, this is for security purposes.
If you want files to be created as foo:foo, then you would need a user foo with a primary group of foo and have the smb.conf file entry:
Code:
guest account = foo
I dont have samba configured at home so I can't test the theory, please let me know if this does or doesn't work as anticipated.