There were Templars in Redcliffe.
When Meredith 's sister went abomination she still managed to kill 70 people with templars. there.
Plenty of templars in Kinloch Hold too.
There was a powerful noble and a wife who was determined to keep her son out of Chantry's hands because she feared what handing him to the Circle meant, so the templars were never used, the right specialists never called in before it escalated, and an incompetent brought in by Loghain (and the timing there is really, really off) meant to tutor Connor, well that was Isolde was told, but actually was there to poison Eamon, and also Isolde sending pretty much all the knights away before the situation escalated. Thus, the templars were never called in because Isolde didn't want them to be.
Meredith's family never even sought a tutor but felt it was better to keep their child safe because they feared what the Circle would do to her, thus she never got training and was easy prey to the demons.
And the Templars in Kinloch Hold held the upper hand until Justinia, Leliana and others broke the mages out, and it was the templars who dealt the first blow while the mages were not breaking any Chantry decree or laws.
The issue in all these cases has been that fear of the Chantry controlled Circles, and the Templars, keep mages from getting trained, or the templars/Lambert overextending what they are supposed to do and making an already tense situation worse.
But, the scenario people are suggesting isn't that families keep their children away from the Circle or any form of training so they can live in town, it's that once the mage in question has been trained and can control their powers safely that they can live in the outside world, which is what, pretty much every culture outside the Chantry controlled countries and the Qunari has in place with no serious problems as a result.