While it's not that hard to kill somebody that use a Awlpikes, most people don't seem able to do it, because it attack way to fast.
Unlike most weapon it attack mostly strait forward, this mean that it will hit faster then any weapon that need to be swing. For some reason you can also recover from a blocked attack much faster and really spam attack.
While i would agree that people that use it have no shield and take a risk that way, in the hand of a good player you can become unstoppable.