Are all master degrees fully funded for North American universities? For whatever reason I had the misconception that graduate study is fully self funded except for some opportunities for scholarship or, in extraordinary circumstances, a full ride scholarship. So you can imagine how surprised I was to find out that certain amount of money is automatically given on an annual basis for graduate studies. 

Is this true through out North American universities? This sounds like a wonderful opportunity wonder why not more people go on graduate school.
Most master's degrees are not fully funded (or even funded at all) in the United States. Funding varies by of study field. Some fields, such as business, will rarely offer funding, while others are more likely to. 

Perhaps you have been looking at PhD programs in math and science - these do tend to offer funding. But that is the exception, rather than the general rule.  At the master's level, funding is more rare even in these fields.