A Digg user claims to have gotten in contact with Joanna via her Myspace (before it was made private) and had a conversation with her about her poor attitude. She says it was all just a lark:
43 things not to do at mcdonald’s
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UPDATE: 43 Things Not To Do At McDonald’s Pulled. We Restore!
Apparently, that 43 Things Not To Do When Visiting McDonald’s list, illuminated by the sober dawn of reflection, was deemed not a wise career move by Joanna from Walker, Louisiana.