Registering your SQL Servers participating in availability groups by availability group listener name is the alternative method for the following reasons:

• You can perform backups and recovery on databases on the primary replica of the availability group.
• Your backups are performed based on the availability group properties' backup preferences.

Keep in mind:

• Only the listener's name needs to be licensed.
• Policy jobs in the SQL Server agent on the new primary need to be recreated in a failover event.