Wouldn't you need a conductor for the electrons to be able to flow from one object to another?
[Additional Info] If a metal object with excess electrons comes into contact with a neutral metal object, electric charges will flow until both objects have the same charge.
When an insulating charged object ( e.g. PVC ) comes into contact with a neutral metal object, how can the electrons move through the PVC to the point where it is in contact with the metal object?
I would expect the amount of charge transferred to be extremely small compared to metal objects, possibly too small to detect using simple experiments, but this is clearly not so.