[discostu]

They don’t have a monopoly on any commodity. With the Whole Foods purchase they now have about 2% of the grocery business. Not actually even a little bit scary.

[oh8eleven]

They don’t have a monopoly on any commodity.
Actually, they won't need one - all they have to do is have a monopoly in a service area, say all the red states, then decide they won't sell a given food product.
Look at what the cable companies have done - agreed amongst themselves not to "invade" a competitor's area ... and they can gouge their customers all they want.