The answer to this is NO. Even though this does not happen very often, there are people out there that will try and take advantage of you. They will buy one ticket and make multiple copies. The problem with that, is that we scan all tickets at the gate and our gate personnel will be notified instantly if that ticket has already been used or is invalid. Also our system allows us to flag certain ticket types that we feel require additional information before being checked in. Before all major events, we go through all the orders and flag anything we deem might be a fraud or looks suspicious.
DO NOT BUY AN E-TICKET FROM SOMEONE YOU DON"T KNOW