That is correct, people were using a remote to crack the bottle valve. In the end of the 90's police enforced and ticketed for the bottle racked and filled. Did not matter if the valve was open and/or if the system was charged. Then early 00's people made fake sub boxes with bottles in them to hide. I was never into the nitrous scene that much. Really do not like giving the police a reason to disturb me. So my integra has the bottle removed. The solenoid box , and lines are all hooked up. My nozzle is underneath the plenum and cannot be seen from above.
Another thing they ticket is filling race gas directly to the vehicle at the pump. You have to pump into a gas can first.