The primary reason for the switch is to stop people revving the engine and the Swing taking off while no one is on it.

Actually the reason for the sidestand switch is to prevent someone from riding off with the stand down. There have been many people, and one fatality I know of, that have been injured by forgetting to retract the side stand. If you are inadvertently riding with the stand down and turn left it's very possible to have the rear wheel of the bike lifted off the pave ment as the bike tries to pole vault on the stand. Nearly guaranteed to drop the bike usually high siding it. Most modern motorcycles have the switch to prevent this type accident. On motorcycles the switch is set up so you can run the engine on the sidestand but not put it into gear. Normally it's in series with the neutral light, no neutral light, raise the stand and the engine quits. This doesn't work with a CVT since there's no neutral so it simply prevents the engine from being operated with the stand down.