Why are online fraudsters always so surprised, so shocked, and their reaction so disproportionate when someone finally exposes them?

Her screen isnt switched on.
Her screen isn't switched on.

Don't people like this (i. e. fraudsters, catfish, scammers etc.) understand that eventually they'll make a mistake and be found out? I ask this question because on GAG I've been "unfollowed" by one, and blocked by another, for simply pointing out the patently obvious to them, that the photos they were expecting people to believe were theirs were actually not. It's very easy to search for the true source of a photo online. I guess they didn't know that.

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+1 y
I know, I've got a picture of Scarlett Johansson as my profile photo. It's part of a bet that I've made with someone, kind of like an experiment. :)
Why are online fraudsters always so surprised, so shocked, and their reaction so disproportionate when someone finally exposes them?
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