How much of our taxpayer $$$ were spent for Michelle's purchase of her leafy greens?

Here's how Michelle Obama handled this very predicament Thursday afternoon:
The Secret Service and the D.C. police brought in three dozen vehicles and shut down H Street, Vermont Avenue, two lanes of I Street and an entrance to the McPherson Square Metro station. They swept the area, in front of the Department of Veterans Affairs, with bomb-sniffing dogs and installed magnetometers in the middle of the street, put up barricades to keep pedestrians out, and took positions with binoculars atop trucks. Though the produce stand was only a block or so from the White House, the first lady hopped into her armored limousine and pulled into the market amid the wail of sirens.

Then, and only then, could Obama purchase her leafy greens. "Now it's time to buy some food," she told several hundred people who came to watch. "Let's shop!"
Obama, in her brief speech to the vendors and patrons, handled the affordability issue by pointing out that people who pay with food stamps would get double the coupon value at the market. Even then, though, it's hard to imagine somebody using food stamps to buy what the market offered: $19 bison steak from Gunpowder Bison, organic dandelion greens for $12 per pound from Blueberry Hill Vegetables, the Piedmont Reserve cheese from Everson Dairy at $29 a pound. Rounding out the potential shopping cart: $4 for a piece of "walnut dacquoise" from the Praline Bakery, $9 for a jumbo crab cake at Chris's Marketplace, $8 for a loaf of cranberry-walnut bread and $32 for a bolt of yarn.

The first lady said the market would particularly appeal to federal employees in nearby buildings to "pick up some good stuff for dinner." Yet even they might think twice about spending $3 for a pint of potatoes when potatoes are on sale for 40 cents a pound at Giant. They could get nearly five dozen eggs at Giant for the $5 Obama spent for her dozen.
"I have never seen so many people so excited about fruits and vegetables!" she said. (Must be the tender baby arugula.)
She spoke of the global reach of her cause: "The first thing world leaders, prime ministers, kings, queens ask me about is the White House garden. And then they ask about Bo."
She spoke of the fuel fed to the world's most powerful man: "I've learned that when my family eats fresh food, healthy food, that it really affects how we feel, how we get through the day . . . whether there's a Cabinet meeting or whether we're just walking the dog."
And she spoke of her own culinary efforts: "There are times when putting together a healthy meal is harder than you might imagine."
Particularly when it involves a soundstage, an interpreter for the deaf, three TV satellite trucks and the closing of part of downtown Washington.  (see full story here at Washington Post)