Being a part of a society means not only freedoms, but responsibilities. You're responsible for following the law. You're responsible for paying taxes (you know, those things that pay for all the free stuff you're demanding) and sometimes you're responsible for defending the country that guarantees you those freedoms.

The US has a large population and is able to field a military with only volunteers (at the moment. This wasn't always the case, and the draft can be reinstated if necessary). Smaller countries would not be able to have a military at all without mandatory service. Their freedoms would be moot if they were invaded and conquered.

Demanding freedom and shirking responsibility is the act of a child.