i can say that 99% of all ride accidents do come from the actions of riders.as i was a ride operator for 16 years.with only 1 accident on rides i operated and that was the rider trying to change seats while the ride was in motion.and as far as operators being drunk or on drugs you are more likely to be hit by a drunk driver then to find a drunk ride operator.and you will find drunk or doped up workers in any field of work.