Striking Ramp?

During competition we noticed teams striking the ramp causing enough vibration to empty the balls from the cutouts. It is very effective. Is the striking of the ramp a violation of the G6 General Game Rule or any other rules?

G6: Drivers are prohibited from making intentional contact with any Field Element or Robots during a Match. Any intentional contact may result in a Disqualification. Accidental contact will not be penalized, unless the contact directly impacts the final outcome of the match. This type of accidental contact may result in a Disqualification.

G6: **Drivers **are prohibited…

This is not about robots, but drivers. Robots are allowed to make contact with field elements.