Trellis Ideas

There is a note that all unpaid tickets are removed from guest's carts immediately upon event end. We depend on the option to add a ticket to a person's cart at the door and collect payment from them later. Can this be an optional setting or one that can be disabled? I would have no way of tracking who I needed to collect payment from if my volunteers added a person to the event and that ticket was deleted before payment could be made the following week.