The Allow Local User Login tooltip in Services/FTP states it's required if Anonymous Login is disabled. However, one can still save the service without either enabled, so it's not actually required (it's just that you won't be able to connect). Furthermore, only Allow Root Login can be enabled, so it appears both Local User and Anonymous can be disabled, but they are required when using the path.
Should Allow Local User Login be required if Anonymous is disabled? Should the path field be tied to one of these? Should the service be able to save with none enabled?