If Bush bombs Iran and those bitches shut down oil coming out of the persian gulf, your grocery bill might get that high. 40% of the world's oil cuts through there, and Iran has vowed to mine the shit out of that water. US military announces they think they can stop this. Time will tell, I spose. At the very least, bombing iran stops their exports and we see a spike in oil prices (which in turn affects what it costs to produce and deliver foods).
If oil is $170 or $200 a barrel, a $500 food trip isn't impossible.