I will tell you how they did it to me at the Wembley semi final last season.
You get to the turnstile and when you present the barcode it gives the message "ticket blocked, go to the ticket office "
You go to the ticket office and they take the ticket off you and check your id and then give you a new already printed ticket back.
They have a list of tickets that they have blocked and who's the original owner if that doesn't tally with your shown id,you aren't going in.
This is what happened, so don't be telling all and sundry it doesn't happen because it does and I can assure you it will definitely happen this season .