Apologies for getting late back to you.
On higher notes, you are correct it helps you to store user-specific attribute along with his/her session on the server. Apart from this its also have admin API to manage the user session through which you can expire and generate new session for a user.
In some of the cases, it helps you to check the user session is valid or not. e.g: You have a case where you want to run your code only for verified users with their valid identity. In such case, you can use admin API to check the session of the particular user and take certain action.
Let me know if above information helps or if you need any other help from our side. We will be happy to help you!