People are quite reasonably more afraid of attack vectors that can affect huge numbers of people all at once, especially when the attacker could be anywhere in the world.

One obvious example of why that's reasonable is the recent ransomware – sure, you've always been able to easily extort $300 from someone, but now you can take money from a lot of people, and not get caught.

Hacking is something that is getting more and more likely by the day. First, WannaCry infects the world over and knocks out a hospital system. What's next? Pacemakers going offline? Insulin pumps being hacked? Hell, cars can already be hacked from a distance, internet connected cars aren't raising a risk factor by much, aside from it lengthening the distance at which you can do the hack.

Now imagine that on every bridge. It only takes one car to bottle up a lane.