Is it really a sub-panel if drawing from the power pole with meter

100 amp 220v Pole power to main panel in residence vs 30 amp 220v pole power to main panel in shop.
Both on same pole meter.

Here is my question and after reading must, I am still at a loss.

Both is pulling from the pole.
The shop panel is not pulling from the residence main panel so really not a sub-panel.
My main box panel at the pole is a 100amp 220v breaker that goes to the residence.
My main box panel at the pole is also a 30amp 220v beaker that goes to the shop.
Is the shop panel be treated as a main panel or a sub-panel?
How to ground the panel in my shop?