IJWTF, i believe the point the poster was making was that the gate agent took their boarding cards. This is why they had no cards.
Perhaps the F/A was new, could have been her first time doing flight on her 'own' and she's thinking 'oh god i stuffed up and now Osama's mates are on the plane'
(well we all know what it's like to be new don't we?
)
Or perhaps she's a Pruner and has been reading that thread about not checking boarding cards...
