This is honestly pretty smart on the part of the fascists. A big portion of what is so effective about the resistance is that it's founded on strong community action. Neighbors helping neighbors, because it's the right thing to do.

Posing as a neighbor in need makes that act feel riskier. It changes the calculus, just a little, in favor of not helping your neighbor. They achieve their near term goal of getting their victim, but there's an even more valuable (to them) effect of weakening community ties overall.

Time to double down on looking out for your neighbors.

EDIT: Looking out for them so you can help. In case that wasn't clear.