Whats to stop people from printing fake and/or duplicate tickets?
We have numerous safeguards against that in place. For one thing each ticket has a unique bar code which only validates once. The odds of guessing one are small. The odds of guessing one for a reserved seat are infinitessimal. If someone duplicates a ticket, the first person to use it will validate, any other copies will raise an alarm. Users need a code to access their tickets. This is the exact same technology that the big ticket vendors use.