Some people like neat little boxes for others. It's the only way their narrow world can make sense.
Laziness, ignorance and fear.
Two words.<br />
We tend to think of people as archetypes, to help us understand the complexity of others. The problem is: most people simply do not comprehend all the archetypes there are and that people are never just 1.<br />
They try to push people into just 1 or 2 archetypes, wich is either really dumb or very lazy.
Unfortunately people have a habit of making assumptions due to ignorance and prejudice
It's because they ASSUME and you know what that means... :)
Easier than actually using the knob on top of their neck.