There is such a thing as altruism. There is also creativity for creativity’s sake. So, I don’t think the profit motive is the primary motivation for human action, especially when people are removed from the capitalistic framework.
Take the nuclear family for instance. Within the family, arrangements are largely communistic in the sense of “from each according to their ability, to each according to their need.” This is what David Graeber refers to as “the communism of everyday life.” And it extends beyond the nuclear family in rural communities. If I need a trailer and my neighbor has one, he will likely let me use it free of charge. If my neighbor needs help cutting up firewood, I will lend him a hand free of charge. In the rural environment, economic relations are not strictly “economic” in the market/money sense of the term. Rural economic relations tend to be more familial and communistic: from each according to ability, to each according to need. You do things because it is the understood ethics of the country culture, not because you will make a profit or acquire property thereby.
I remember a time when I was young and there had been a bad storm that knocked limbs down everywhere. I went over and cleaned up the yard that belonged to the old lady across the street because I knew she couldn’t do it. I wasn’t expecting anything in return. I wasn’t even expecting to put her in my debt or create an obligation, as with gift-economy theory. I was merely doing the right thing because it was the right thing. People aren’t going to just stop contributing to society if the profit motive is taken away. In fact, most of the people that are really contributing to society today are not motivated by profit at all.
When I look at people that I see as those who have created the most value in terms of their contributions to humanity, I think of people who were almost certainly not very motivated by profits. Was Charles Darwin motivated by the prospect of profits when he was studying and writing about animals he observed in his travels? Was Louis Pasteur motivated by the prospect of profits when he discovered and educated the world about pasteurization, fermentation, and vaccination? Did Oscar Wilde write his poetry in prison because he thought he might make money from it? Was Mahatma Gandhi motivated by profit? Was Martin Luther King Jr?
Furthermore, I have not said that one ought not to have personal possessions. I have not even said that one ought not to accumulate lots of personal possessions. I have merely said that there should be limits set to such accumulation, and that limit should be the point where acquisitiveness starts to impoverish others. And I think this means that the most just arrangement is bound to differ depending on the “particular circumstances of time and place.” Hoarding a certain amount of possessions may be acceptable in New York City, but that same amount of hoarding of resources as private property could be highly unethical in West Kurdistan where resources are so scarce that any amount of hoarding might cause others to starve. Furthermore, I don't think that an individual's property right should keep the community from being able to limit the sort of actions he can take with his property. If you own a piece of land, your community has a right to prevent you from dumping toxic waste into the soil. Property rights ought not to be absolute.
I look at this issue more anthropologically. Property is a human convention. And property arrangements can be altered to suite the particular needs of a particular community at a particular time. The problem is not private possession in itself, but the idea that private property ought to be absolute or that propertarian NAP ethics can somehow serve as a solid theoretical basis for human ethics in general.