It's often easier to allow people who are lying to get away with it because of the effort it takes to unravel their plot and the fact that you're then playing into their speculative hands. I suppose this is what they want, however, although the crafty ones would likely rather play out their defence. As you annoy them by not taking their story seriously while believing it, they annoy you by concocting increasingly elaborate farces the acceptance of which may have severe social and professional consequences. It comes down to who is the most stubborn, the lazy gatekeeper or the silver-tongued patron, and who can hold firm to their determined constitution more deviously, the winner producing a virtuous act or a dedicated employee.