We have network cables running throughout the house and no two electrical outlets of the scattered connected equipment can have the same ground potential.
Thus, aside from reducing EMI/RFI interference which could potentially be an issue there is CMRR which is often overlooked. It has been suggested that many receivers actually have very poor CMRR and that ground voltage differences can easily be large enough to exceed a receiver's common-mode input voltage limits using unshielded twisted-pair (UTP) network cabling. By using shielded twisted-pair (STP) network cables grounded at both ends, the ground voltage difference creates a shield current and its resultant magnetic field induces the same voltage over the entire length of the twisted pairs enclosed within. The polarity of this induced voltage in STP cables helps to reduce common-mode voltage at the receiver.
If a network switch does not utilize a ground shield for its ports then the CMRR benefits of STP network cables are lost.
YMMV but this is why we ran the STP CAT 6a cabling. We did run UTP CAT 6 for the video streaming devices to eliminate any potential ground loops that might be introduced into their connected audio systems. We may try running STP CAT 6a cabling to them at some point and give it a try, their network ports use transformers so they might not introduce a ground loop to the audio systems.