Because you have no say in how tax monies are spent, that's how taxes work. Then there is the rule for rulers[1], then because that's how USA rolls (have a look at the history of the country and you'll see that this is not an isolated event), also amusing ourselves to death[2], politics as usual, business as usual, capitalism, unsustainable economy based on growth and a bunch of other reasons, but mostly the great USA land of free yay!

[1]: http://www.cgpgrey.com/blog/rules-for-rulers [2]: http://citizenactionmonitor.files.wordpress.com/2011/06/amus...