What with that foreshadowing of Frieren's death?
The author really know how to be subtle.
@SotiCoto
The people here seemed to have been living in this dangerous region for a long time, so maybe they already have something prepared in case something happens.
The other cities didn't allow passage maybe because they didn't believe it to be safe enough.
Also, there's always someone who will keep going even if it isn't allowed.
The old man didn't fit in that category since he seemed to be the inhabitants of the town.
Lastly, the fact that there's a city in a region that was deemed dangerous by many made its residents a bit different than others (maybe, I'm sure that I still lack something, but I think it is enough me rambling).