Of course, a "sprinting suspect" is more likely to give an overall picture to the public which allows the security staff to keep their job. Or at least their face.
I recall that on 22 July 2005 we were all told that Jean-Charles de Menezes had vaulted the barrier at Stockwell tube station while being pursued by police, wearing a big padded jacket with all wires sticking out and everything.
Only later did we discover that he had a ticket, walked calmly on to the train, dressed completely normally for the time of year. But of course by then he'd been shot in the head 7 times, so someone had to try and cover it up.