How do you know these are "hall passes" and not simply general permission for mages to come and go as they please? They pass their Harrowing, they've proven their not idiots who light to shoot lightning at people who annoy them, let them enjoy themselves!
And no, not all Circles were that permissive of course, and Kirkwall was the worst of the worst. But White Spire seemed to have gotten as bad as it did after Anders blew up the Kirkwall Chantry, followed by attempts to kill the Divine by blood mages, and the whole Ghost of the White Spire thing didn't help matters. Tensions were high.
In the beginning of Asunder, Adrian and Rhys are talking about how they used to go shopping in Val Royeaux, but that they haven't been allowed outside in years. All this happened *before* Jeannot tried to assassinate the Divine at Celene's ball.
The timeline was:
9:37 Anders blows up the Chantry, mages of the White Spire are now restricted to the tower
9:38 The College of Enchanters votes against secession from the Chantry
9:38 The Chantry immediately disbands the College of Enchanters, revokes all travel privileges, and revokes mages' right of assembly
9:39 late autumn: Empress Celene hosts a ball for the Divine where Jeannot, an enchanter, attempts to assassinate the Divine
9:39 late autumn, a week later: Rhys and Evangeline are ordered to investigate Pharamond's disappearance
9:39 winter-9:40 early spring (date uncertain): Rhys and Evangeline return and the White Spire falls
It's possible that the White Spire was unusually restrictive... but it's also possible that Vivienne was stretching the truth because it suited her purposes. I really enjoy Vivienne as a character, but one of the things I appreciate most about her is that she is entirely capable of manipulating others to get what she wants. Yes, she absolutely does want to save Duke Bastien's life, and I firmly believe that she is primarily motivated by affection for him... but her first act after Duke Bastien's death is to persuade Duke Bastien's sister, an influential cleric, and his son, a key member of the Council of Heralds, that she has the Inquisitor's backing and support. She is cementing her position and ensuring that Duke Bastien's death does not have a negative impact on her social standing. She has mastered the Game, and all attendant politics.
You also have to remember that when Vivienne is telling the Inquisitor all this, it is long after the fact. The Circles are gone. Anyone who might conceivably contradict her is either dead or in hiding. Do I think she's lying? No, not entirely. I'm sure that at one point (and for certain mages), travel required nothing more than permission from the First Enchanter. After all, the mage Warden needed only permission from Irving to go with Duncan. But I doubt that was the whole story.