What's wrong with a patriotic message?  

I don't want the DOD (or any government agency) wasting taxpayer money, of course.  Whether this is a waste of money is debatable.  They use it in part for military recruitment. A form of advertising, like the ads we see on TV for branches of the US military. 

Are city parades a waste of money?  July 4 fireworks displays?  Perhaps.  This falls into the similar category.  There are certainly worse things to waste money on than patriotic displays for OUR OWN COUNTRY, of course.