Something Feels Fishy
This case makes me wonder if the muggers were already in the area. This would make intuition rather than observation. You may frequently detect when others have harmful energy; if they intended to assault an entire party, they would have been obvious from a long way off.
So, was this a violent encounter? Or did they simply rummage through purses and pickpocket wallets before leaving the premises without giving it a second thought? I mean, the end result is the same, but the method used matters! It would be far more frightening if they robbed people with a gun or knife rather than sneak about.