I never said the only motivation people have is personal greed.

Taxation is literally a mugging. And you are in error to assume that governments cannot exist without mugging. Businesses provide services and charge for them. A government could do this as well.

don't speak for libertarians if you aren't one. If you are one, you've failed to apply the zero aggression principle.

You also seem to fail to distinguish between using violence defensively against an agressor, which is moral, and using violence offensively to steal from someone (eg: taxation) which is immoral.