The speaker uses eating as a way of talking about how we take in the world. "Omnivore" suggests someone who consumes everything, and here the stomach does the exploring, moving "mole-like" through most of what the world has to offer. The speaker is stuffed with "meat and visions," so both physical appetite and imagination or experience have been fed.
Yet the feeling is not contentment. The speaker is "full better than full" and still dissatisfied, not with the food but with "the method used." The last lines describe a cycle of getting hungry again and again, then taking pills. That detail is open to interpretation: the pills might be a dull, mechanical fix for a deeper hunger, or a sign that this endless consuming has become a routine rather than a pleasure. The mood is wry, a little weary, and quietly restless. The speaker has had plenty, and plenty doesn't seem to be the answer.