If you'd like the customer to receive emails/tickets after adding a Product to a basket, you need to activate Print Rules on the Product Settings page.
NOTE - A Product must have the same Print Rules activated as the ticket items in a basket in order for the Delivery Method to appear. If products and tickets have different Delivery Methods, then none will appear to select in the booking flow.
Because of this, it's worth adding Product Merge Tags onto your standard Email/Ticket templates so that there's transaction info for your tickets and Products in the same email.