Competitive Sports are a good training ground for the major aspects of competitive capitalism. There is a reason that the liberal New York Times has the Sports pages at the end of the Business Section...They are both advocating the same value system...Competiton is Natural and Winning is everything...Neither of which is valid.
Competition is not only natural, but in its finest form it becomes cooperation.
Competition starts in the very first moments of life as the first cells compete for the chemical "food" that will change them either into Neurons, or Support cells. During this stage cells have even developed chemicals that they release that will keep other cells from grabbing the valuable chemicals that they are using to feed themselves, to change from a stem cell to a specified cell, thus it settles the strongest to become the neurons, the weaker support cells.
To say that it is unnatural to compete denies almost all forms of life in study and to misunderstand it so completely that it becomes a negative in itself, rather than in its application, is denying the nature of life itself let alone human nature. To deny it in the beginning stages of a human life will create a situation where either competition becomes prevalent in its negative applications as they were not taught the different forms, or an unsettled human unable to compete even on the simplest levels standing in confusion as they find they are constantly removed from the positions that they value, but have not the tools to reach them.
Now we can get into whether competition can be cooperation. Outside of team sports it is in an ecosystem is where you will find the best examples of this. Or the easiest to see. Plants fight for the most light, using that same chemical warfare, or simply using height to get the most. However, the taller plants often cannot survive without the other plants that are competing with them. This happens with predator/prey as well. And even within predator packs and prey herds themselves.
Attempting to simplify competition and make it always negative simply denies a far more complicated precept of life, and begins to deny facts of existence for an extreme view. Such as Utopia, Communism, and for those on the extreme right Anarchism, or a true "free market" economy.
Governments compete to be the first to space, the first to the next step in medical science, the first to the best and most efficient military... Each of these brings forward scientific advances that if left to a total free market economy would take much longer to be brought forward, many would never come to bear because the cost-basis would not be profitable in a foreseeable future. This too can be cooperation in the end as it advances more than just the government itself, and benefits far more than the one society.
It is far more complicated than just saying, "Competition is not natural." which isn't even reality, there is no evidence that any life would have evolved above a single cell without competition. Competition is more than natural it is the basis of evolution, of how we became complex organisms to begin with. To deny competition in nature is beyond odd, it denies reality.
In a team, as in the NBA, environment there is competition within the team as well as between teams. Each competes for the valued positions, this makes the entire team better and again presents another example of cooperation within competition. Each works together to become better as a whole as well as better as an individual, just as in the predator pack mentioned above, and this benefits the entire team/pack.
To say that there is no benefit in any competition or that there has been nothing gained positive from economic competition prevalent in a capitalistic society denies proven success. Is there something better? Probably. Will it include competition? Even more probably.