The only real justification for scanning is to prevent people buying tickets on line and printing multiple copies to use on a T20 night, assuming the system is set up in such a way to identify it happening and alert the people at the gates which I very much doubt. As I only use a membership card or a proper ticket printed by the club, I make every effort to avoid scanning particularly if there's a queue for it. Just walk in waving your membership card, the border guards won't do anything.