At Air Canada you only have to show suitable picture identification to prove who you are (e.g. driver's licence, passport etc.) when picking up an e-ticket. It doesn't make sense to have to show your credit card that the ticket was bought on. I have at times travelled on e-tickets purchased by government through a travel agency--all I had to show was suitable identification--they didn't require government to show up to say the transaction was OK

. . . I thought the US was the most technologically advanced nation in the world