Yep, the premise of this is pretty ridiculous. Out of 80k they only identified 2700 homes. How many of those are actually within a reachable distance and how can you be sure those people also live alone. I'd bet a large percentage of users posting on Instagram probably also live with their parents and therefore there's a chance the house won't be empty.

So what are you left with? A few hundred? That's assuming the average burglar would even bother to do any of this as opposed to just staking out a house for a few hours with poor security.