No. it is not necessary to create the directories with the name prefixed with SubUserId. You can create any directory with any suitable name.
Subuserid: Sub-user id can be a unique ID or number or company name. Suppose you have so many users, you can save each user based on the Unique id such as User1, User2, User3, etc.
Subuserid can be set differently for the Staging environment and different for the Production one. It can be "Staging_8.0.0" for testing or staging application and "Production_8.0.0" for a production application.