The W is for Walker as in george W Bush, but the picture on the label tries to imply that it stands for Washington.
Quote from the Washington biography on whitehouse.gov
"To his disappointment, two parties were developing by the end of his first term. Wearied of politics, feeling old, he retired at the end of his second. In his Farewell Address, he urged his countrymen to forswear excessive party spirit and geographical distinctions."