Also, a face-to-face deal would be a physical hazard.
I would not even think of doing this; for all we know, these people are thugs or a syndicate who victimize traders and investors. Even if it's done at your place, they will do surveillance to track your activity. When it comes to trading, exchange is the best place to do it; never do a face-to-face with strangers; there are many offline scammers looking to victimize people.
There are ignorant people out there that are dumb enough to fall for this.
Why wouldn't the user just buy btc from an exchange unless they were just looking to scam or steal from someone? Smart people think about that and the not so smart get scammed.
Not sure why people in the world have to be so ugly, but unfortunately there's always bad people out there. Stay safe everyone and don't fall victim to this type of scam.