It's a proof of concept example. If you literally stick everything on a tripod out in the front yard, sure it would be stolen. Before that it would also just fall over in the first rain storm or the first time an animal walks by. But no one would take a proof of concept example and literally do exactly that, would they? Because that would be STUPID, obviously, right?
You would mount the swarm kit on the roof, the pi indoors anywhere, the camera anywhere, hidden in the usual kinds of corners and in an enclosure, or just buy a ready-made usb or wifi camera that already comes in an enclosure. You don't literally have to use the delicate, exposed, short ribbon-cable pi camera.
What you do with the knowledge provided by the email is whatever you want. Call a neighbor. Call the local police. Retrieve pictures/video/audio after the fact, automatically saved locally on the pi or on a usb stick that the neighbor or police can retrieve if you can't, to at least identify who it was. Of course you're not going to catch anyone while still in the act. You never were. But you will at the very least be able to call the local police within the hour, and that is a lot. Locations that are remote enough that you need a sattelite connection measured in hundreds of 192-byte packets per month, have very small local populations. Everyone knows everyone else, and every stranger stands out. A few reasonably clear pictures of the people, and/or their vehicle, even without a readable shot of the licence plate but you could probably get that too, will usually identify them with the local police. They will be known to all the locals. And even if they aren't known to the locals, even that is identifying by exclusion. Now they know it was that one stranger that was around that day, or the state police can spot the vehicle on the roads, in the wider area, etc.
This covers everything but Ninjas and ludicrous spy movies. You do not live in a ludicrous ninja spy movie. You live in a world where a couple of local lowlifes, probably just high-school kids, or one of the well known local drunks or idiots, drive their well-known vehicle right up to the door and rummage around in their normal clothes, and sell your stuff to a pawn shop maybe one or two towns away, who you just call up (there aren't 10000 of them in a reasonable driving distance circle, you just call them all, or the police do automatically) and describe your stuff and day of theft and maybe some serial numbers and probably not only get your stuff back but also catch the the guy who took it from the pawn shop records plus your own pictures. Even if you don't get your stuff back, at least you helped by providing data to the police which helps them catch the same people eventually after they do it a couple more times to other people. Even that is worth doing, because maybe you're the one you only provides data and the next guy benefits, or maybe someone else provided data and you're the one who benefits.