When a ticket buyer with a Contact account is logged into their account, they can manage their preferences themselves via the tabs Interests and Personal data.
Interests in the ticket shop login correspond to the Customer Interests that are set for each event on the Publicity tab. We link the public to your categories via the Interests. You have an event where you made a Customer Interest, ‘Rock’ and you have contacts who have the Customer Interest ‘Rock’.
Contacts can adjust their interests themselves when they log into the ticket shop. Stager responds to their actions. So, when a contact buys a ticket from an event marked as ‘Rock’, that person's interests are automatically updated in Contacts.
During the registration process you can ask ticket buyers additional questions and show options: maybe an opt-in to a monthly newsletter. You can then search for all Contacts who have checked a certain opt-in via Marketing - Contacts - Audiences. Contacts can activate and deactivate their opt-ins themselves, using their ticket shop login in the tab Personal details, under the heading Registrations. Read more about opt-ins here.