Sure, we can explain how this works, you just need to subscribe to our educational series on the topic...

It's all about framing the con in a way that gets past the defense mechanisms the OP assumes. Whether this is done with synthetic intimacy, urgency, exclusivity, high-mindedness, etc. depends on the target victim profile.

But, it's always social engineering. The only 100% defense is to assume a deeply untrusting posture that makes social living nearly impossible.