But if you want to protect your bike. You should get them. However, if you have the front hwy bar. That's typically enough for protection on a bike that doesn't have saddlebags. Your exhaust will most likely get scratched no matter what. and the rear hwy bars more or less just save the majority of your bags. That paired with the saddlebag rails work great.
I have sometimes ridden my bike without the saddlebags. The only weird thing was when I pulled up at some traffic lights with the sun behind me. I looked down and the shadow of the rear bars made it look like the bike had Dumbo ears. I figured I could live with that.
If you drop the bike without bars the pipes will take the hit. If you have the bars they don't. I've had a few slow speed u-turn drops without any worry, apart from a bit of embarrassment. I just say, 'old man, heavy bike, not a good combination'. The pipes are in the clear.