I completely disagree with almost all of you. This is our country and wearing a flag t-shirt is not offensive. If people want to celebrate their country's holidays then go ahead, but since this is also their country, don't get offended by the flag they must have proclaimed allegiance to. Unless, they are illegals. Oh, and here is a little fact about what Mexicans think of cinco de mayo in Mexico.
While Cinco de Mayo sees limited significance and celebration nationwide in Mexico, the date is observed nationwide in the United States and other locations around the world as a celebration of Mexican heritage and pride.<SUP id=cite_ref-7 class=reference></SUP> Cinco de Mayo is not Mexico's Independence Day,<SUP id=cite_ref-8 class=reference></SUP> the most important national patriotic holiday in Mexico.