It might initially be easier but I'm not sure if you would get very far with the stolen goods.
Everyone was laughing because "ha, that idiot stole a thousand GPS trackers, he's the most tracked criminal ever!" But of course every single one of those trackers was in sleep mode, and the only tracking bug was not part of the shipment. Sure, he was caught red-handed within half an hour while a police dispatcher watched a moving dot on a google map, but he was only being tracked by a single device, and we had no way to remote-active the other thousand.
Just an amusing related anecdote.
I'd much rather do all that than kill an armed truck driver.
Now that I actually am thinking about this more, I'd just get a sniper rifle and shoot the sensor units on the truck so it would be incapable of driving further (as opposed to throwing a mattress onto the road).
But again, I'm not in the business of robbing trucks. I'm just saying I'd rather rob a robot than a person. I doubt robberies are a big concern for driverless trucks.
Trucks are big. They're also not particularly flammable. Hard drives are small and easy to fireproof.
> only commit crimes in a wireless dead zone so no data is transmitted outside
This put you pretty far out of your way, and you're eventually going to have to bring a truckload of goods back from the middle of Idaho or wherever. Plus, trucks can carry pretty big antenna.
> (or better yet, use a police stingray so you can do it anywhere)
This doesn't really work that way, and also this is an additional major crime. Plus, people are looking for these.
> and put all cargo inside a faraday cage
That's a big faraday cage. Plus, what happens when you have to take the cargo out of your truck-sized theft apparatus and fence it?
> I'd just get a sniper rifle and shoot the sensor units on the truck so it would be incapable of driving further
I doubt there's anyone on earth who could make that shot once, much less 5+ times in a few seconds. A truck is moving 60+ MPH and the target is a few inches across.
More to the point, I think if we're trying to secure the use case of "truck the same as it has been for 30 years gets a black box put in it" we're doing it wrong. After not too long you just flat out won't be able to get in, even if you do stop the truck from moving. You won't be able to drive it anywhere - what need is there for a cab on an auto-truck?
Serial killers have it easy: they can bury the body. You can't bury goods you need to fence. At some point there will be a pattern.
If the truck is unmanned, it's burglary (or theft, since a truck isn't a building).
They typically carry different penalties, and the difference is even more stark if you happen to have anything that could be considered a weapon on you when you do it.
Besides that, it is (likely) easier to trick an unmanned truck into stopping as OP mentioned. A person would easily recognize what's happening and it would be easier for him to just drive around the obstacle. It's not as easy to create an AI that can "think" around things like that. Besides that, I hear truck drivers are often armed. I would guess that punishment for property crimes is less severe than armed robbery against a person, but I don't actually know.
In the grand scheme of things though, I think this is a negligible concern compared to all of the other problems self-driving trucks have to solve first.