good greed: being motivated to make lots of money by being productive, resourceful, efficient, adaptable and setting up win/win scenarios
bad greed: stealing, placing the safety of others secondary to making money, manipulating people for money, coercing people for money
Libertarianism does not support bad greed (as defined here). most Libertarians would support legislation preventing stealing, coercion, endangering the lives of others and fraudulent activity.
if someone wants to sit on a pile of $50,000,000 that they earned from producing quality products and services that benefited people, WHO CARES? that's their choice. desire and morality do not need to be opposed to one another. why not embrace a philosophy in which they work together, people get maximum freedom and those who who steal, disregard other's rights, coerce and fraud are punished?