If you want to send your sell transaction for each outlet to the customer as the receipt of the sales transaction, you are right to use this to help you to hide the head office if that is necessary in you business. In this feature you can send a receipt according to each outlets.
1. Go to Outlets Menu
2. Choose the outlet. For example Outlet1
3. Go to configuration>Email. Fill 'reply to' with outlet's email, after that click update button