Yes, it seems they can just remove the dongle.

But, what if the driver doesn't know it is there? BMW has USB port, but it is in the back of the center console and you would have to lift up the lid first.

More importantly, if someone wanted to "hack a car" to cause them to crash, I am sure you could connect it some place where the driver wasn't aware it was there.

What is worse, Verizon has to comply with the NSA. Now that will include your car. All it is basically is a 4G wireless connector, making your car connected to cell towers. They can make your phone a device they can listen to, don't think that they won't turn your car into the same thing.

You all have seen the street lights that have microphones now, right?
If you have an Xbox Kinnect, then you home is not private, just look at the Microsoft patent if you doubt it.

There are making it, so you can't be anywhere that they can't listen to you.