Is greed good? Is greed a human instinct? Why are some people inclined to hoard?
For some individuals, greed and selfishness are much more commonly displayed than generosity. So, it might be fair to say greed feels more natural for some. On the other hand, most might say they favor unselfishness.
This discussion depends largely on the social nature of humans. Sure, we're all individuals with our own prerogatives, but we can often gain more by cooperating within our community. Working together with the people around us is usually mutually beneficial for all.
There is an inherent conflict between selfish behaviors (like greed), and the equity instinct – an instinct among most communal animal species, not just humans. Believe it or not, that conflict suggests we are naturally programmed to have an instinct to share resources equally.
Now that's something worth pondering.