I assume with the throwing things we're talking about some humanoid robot that generally mimics human capabilities, (but exceeds them obvs.)?
I think there are 2 ways things could go in robotics: Either we manage to get really good at humanoid robots, then we use them for everything (this is easy, because we don't need to redesign all our human tools) the other option will be that humanoids are too hard/expensive so specialist robots for many roles will be developed, and the ability to throw will only exist in robots where it is needed, or where it is a by-product of their designed function, in which case it will be less of a concern.
Obviously if your goal is war or violence and you have humanoid robots it would make sense to arm them with guns, but it might well make more sense to have armed quadcopter drones instead of humanoid robots. We have a lot of testing to do to figure out what makes military sense in a robot war.
This does raise the idea that many places may end up restricting robot ownership, as firearms are restricted. Even if the danger is minimal, some of the wealthy people who own a lot of robots would lobby for restrictions to make their robots more valuable and create barriers too entry for their competition.
In terms of other ways to turn theoretically peaceful robots into riot bots:
Larger Quadcopter style Drones can also be pretty heavy so they could deactivate themselves and fall on people, or ram them in the face at max speed, oh also they are basically covered in rotating knives, so that's an option.
Driverless flying passenger drones are bigger, heavier and have rotating swords attached, and would have the added benefit of a confused and terrorised passenger/hostage, making stopping it more difficult.
Driverless vehicles will allow the "drive vehicle through crowd of innocent people" style attacks, it will take a lot more skills than it currently does to set it up, but much less chance of being caught, and the passenger/hostage bonus, obviously driverless school buses would need extra security (and they'll need someone there to supervise the kids anyway)
I'd suspect most homicidal religious fundamentalists are not actually the brightest people intellectually so this might be a method of terrorism used more by groups with better technical skills.