The Maryland Food Collective (the "Co-op" in the Stamp) now has a shiny new "The Pope was a Nazi" bumper sticker behind the center cash register.
They are supposed to have a comment box by their microwave, so you might want to drop them a note asking them to remove the sticker voluntarily.
That seems the most polite way of handling it.
You might also try contacting whoever reads the Stamp Student Union feedback form.
Even Benedict-hating Bill Maher has admitted the claim of Benedict being a Nazi is false...and any number of Websites hostile to Benedict will concede that:
There is absolutely no reason to think that Joseph Ratzinger, now Pope Benedict XVI, is now or has ever been secretly a Nazi. Nothing he has ever said or done even remotely suggests the slightest sympathy with any of the basic Nazi ideas or goals. Any claim that he is a Nazi is implausible at best.
The quote above comes from an article on About.com's section on Agnosticism/Atheism. The rest of the article accuses Benedict of distorting his own past and not repenting for not taking a stronger stance against the Holocaust when he was a teenager...but even that author is forced to admit that Benedict was never a Nazi.
What makes me most upset about all this is that I don't know where I am going to buy cheap banana chips to snack on in between classes anymore...
UPDATE: There are Stamp Student Union Feedback forms on a wall outside of the Co-op. You can fill them out and drop them off in the feedback box at the concierge desk (the info desk) upstairs.
UPDATE #2: As of the last time I was in the Co-op, the sign appeared to have been taken down. At the very least, I didn't see it prominently displayed behind the cashier...although if I had, it might have prevented me from eating a whole bag of dates and feeling rather unsettled for the rest of the night...

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