In emergency situations such as this Busweizer packages water instead of beer. They did this for 9-11, they did it for Hurrucane Katrina, along with many other emergency disasters. So its ok for them to support the efforts but not ok for them to pay tribute to the CAUSE of those efforts they supported?
Furthermore this commerical was aired ONE time, it wasn't like they were saying "hey come buy our beer to wash away the pain of September 11!".