As long as the equipment is grounded to the source as required by the NEC they can add as many 'extra pointless' (supplementary) rods at machine.
250.54 Supplementary Grounding Electrodes.
Supplementary grounding electrodes shall be permitted to be connected to the equipment grounding conductors specified in 250.118 and shall not be required to comply with the electrode bonding requirements of 250.50 or 250.53(C) or the resistance requirements of 250.56, but the earth shall not be used as the sole equipment grounding conductor.
Notice that to the NEC Supplementary
is entirely different than Supplemental