What's a common occurrence in your hobby that you think shouldn't be?
For me it's driving while under the influence. If you couldn't tell, I like me some ganja. However I have long since held the belief that it is utterly insane to drive while under the influence of most substances, with maybe nicotine and caffeine being the exception. All too often I see other stoners smoking and driving, which I simply can't fathom. I've only operated a vehicle once under the influence and it was just to move a U-Haul around the block to a different parking spot, which was such a scary experience while high that I refuse to even consider getting behind the wheel again while high.
The rev bombing is when you pull in the clutch and twist the throttle to make the engine rev and make a lot of noise without the motorcycle accelerating. It's completely pointless and it takes away your focus from actually controlling the motorcycle, but you can find countless clips online where someone gets cut off and then proceeds to rev bomb, flip the car off, and sometimes even smash the car's mirror.