It is true that the ground requirement is for static discharge on most telecommunications equipment. You will rarely see any of this equipment installed today that actually requires a ground to operate.
There is one exception: If the device is providing ground start trunks, then yes, a ground is absolutely necessary in order to have a point of reference. The trunks won't work if this reference ground isn't present. People don't usually order ground start trunks anymore, but lots of existing hotels use them.
