As the group gathered before the gates of the supposedly villainous mayor's estate, Arius was more than a bit unsettled by the fact that the warrior bringing them to the rescue of his daughter not only seemed keen on not discussing the details of how that might be accomplished, but also hadn't let slip even once the name of this daughter whom he reportedly loved enough to risk such treasonous acts.
When the old man subsequently opened the gate and proceeded through without encountering any resistance, Arius' unsettled feeling grew all the more. In earnest, he hadn't even considered checking if the gate was unlocked as an option. The rich, even those without nefarious hearts like this mayor supposedly possessed, did not simply leave the gates that separate them from the masses of the poor unattended. To do so was a very good way to find one's self no longer rich.
Glancing about at the specific individuals gathered, Arius also noted that much like the dragonborn, none of those present seemed likely to be locals, even though it was supposedly locals who had been unjustly seized to be carted off as slaves. Indeed, none present besides the warrior noted having a personal stake in this venture. So where were the other friends and family of the citizens supposedly taken as slaves? And how exactly would selling one's own citizens supposed to help the mayor? Whatever value you could get out of them at market would pale in comparison to the lost future tax revenues, the loss of productivity in your village in general, and the unrest that would invariably eventually result. Evil or no, it was simply fiscally unsound... again, a very good way to find one's self no longer rich.
Leaning a bit in the direction of the elven woman who had commented on the concern of spies earlier and whose assessment he'd agreed with, Arius simply notes,
"The wealthiest man in a village full of drunkards lamenting their own destitution... and the vile, child-napping, slave-trading mayor's gates swing open freely and stand unguarded? That's not at all suspicious." Arius then summons his ivory pact weapon into hand in the form of a longsword, before abruptly turning towards and nodding at the warrior,
"It occurs to me that perhaps this isn't business of random drifter such as myself and is best left in the hands of local authorities. Best of luck with recovering your daughter, whatever her name may be.", before he proceeds to head straight back to the tavern, without another word, keeping his ivory weapon closely at his side as he does so.