I've found myself justifying my theiving tendancies with the thought that these poor folks will never use the few potions in this chest anyway, and it's all going to a good cause.
But, yea, I've considered the fact that my characters, honorable as they may be, are not to be trusted with personal property.
Personally, I'd rather see a diversfied assortment of life out there - keeps all the balances right. But I'm not so sure I would be happy that my neighbors were raising something vicious that might chomp on me one day. It's not extermination, is it?
Well, maybe for the giants it will be. But they're all crazy anyway, so can't I justify my ridding the land of them that way?
So maybe morals are based on the expediency of what needs to get done to attain your goals. Fortunatley I have too much empathy to live like that in real life. But it's one of the nice reasons to be able to role play