Warrior and INFJ here as it says under my name. I know my mom to be an ESFJ Warrior, my brother an INFP Warrior and my husband an ENFJ Hunter.
Percentages on the tests can be deceiving because as we mature, we (ideally) develop our lesser "used" cognitive functions more. There are also other factors that affect this. If you have studied the enneagram at all, I believe that if you are a core head type for instance, it is not so uncommon to mistype as a thinking type even if you are really a feeling type and so on. And then there is just the simple fact that a lot of people don't know themselves well enough to answer accurately and that the questions on some of the tests are pretty flawed. Some people also take it wrong. You have to think about how you usually react in a situation, not how you would react at that very moment.
A lot of INFJ's mistype as INTJ's for instance due to tertiary Ti (introverted thinking). Sometimes Fe becomes suppressed for various reasons (maybe due to stress). So it is very easy to mistype for various reasons.
Also, at first glance, INFP and INFJ sound similar, but they actually see with very different functions. INFJ is - dominant Ni (introverted intuition), Auxiliary Fe (extroverted feeling), Tertiary Ti (introverted thinking), inferior Se (extroverted sensing).
INFP is - dom Fi (introverted feeling), auxiliary Ne (extroverted intuition), tertiary Si (introverted sensing), inferior Te (extroverted thinking).
More on the cognitive functions here - http://www.cognitiveprocesses.com/