It's not too big of a leap
I think it is. I'd like to see at least one documented case of this happening before people start demanding that cars be able to move while plugged in. Plus, in the very scenario you describe, the car would still be able to move, no? Attaching a charger does nothing unless you're changing to parked at every red light.
The only time you'd need to drive away while charging is if the attacker walks up while you're sitting in your parked car, or kindly decides to let you get in before doing anything.
I can't find a single instance of someone being unable to escape because of their charger, so maybe let's worry about it if it ever becomes a problem.
To be fair, it does have the most potential to cause harm if you exclude every kind of fossil fuel. And hydroelectric. That said, there isn't a chance in hell I'm going to protest fission if the only alternative is more coal/gas.