The answer is surely that it's not unethical or wrong or immoral to favor one team over another. But there's an interesting issue in the background. At least some views of what morality calls for say that we should be impartial. If I'm a utilitarian, then everyone's pleasure and pain count equally. If I'm a Kantian, then I should act only on maxims that I could will to be universal laws. But in that case, it seems, I can't favor particular people—or particular sports teams. Whether this is really what utilitarianism or Kantianism call for, this would be crazy. It's also an issue that comes up in an important essay by the British philosopher Bernard Williams ("Persons, Character and Morality," 1976.) Toward the end of the essay, he considers a hypothetical raised by another philosopher, Charles Fried. Fried imagines a man who is in a position to save one of two people, one of whom is his wife. Fried is clear that it should be acceptable for the man to save his wife instead of the stranger. But Williams...

I'll admit to being intrigued by the question because it may not seem clear at first what the ethical issue is. We might say: everyone knows that these lists are matters of opinion; in any likely scenario, it's hard to see much harm coming of it. That said, I think there's a little more to the matter. Perhaps we could come at at this way: suppose I put someone on a list like this without doing any serious research. If the setting is a bunch of boxing fans shooting the breeze, it seems like a small sin if it's a sin at all. I know that no one places any serious stock in what's said, and they know that I know this, and so on. But even in a case like this, issues of character come up. I may still be speaking without regard for the truth; in Harry Frankfurt's language, I may be bullsh*tting. Being a bullsh*tter is a kind of a vice; the kinds of people we tend to admire have due regard for the truth, even in small matters. And if it's not just a matter of running my mouth over a beer at the bar but...

Not wrong at all, I'd say. The only reason I can think of for thinking otherwise is that it would amount to not being loyal to one's country. We can agree that there are at least some kinds of loyalty we can normally expect from a good citizen. (Not committing treason is the most obvious example.) That said, it would be very bad if the demands of loyalty went all the way to which side you root for in a sporting match. That would be well down the road to mindless jingoism. In one way it's a small point, but it has some real-life relevance. Noisy, thoughtless accusations of being "unpatriotic" are a far-too-familiar part of political discourse. If we worry that rooting for another country in a soccer match crosses the line, then the worry that we shouldn't disagree with any of our country's policies will seem all too real. That, however, is a disaster for thoughtful citizenship. So root for the team of your choice. Root for them because they're the underdog, or because you like the way they...

Sean has correctly pointed out that part of what you are asking calls for empirical answers. But your last sentence - about sports being the least thing humans ace invented - raises an issue of value. And what you seem to be saying is that since sports produce no tangible outcome, in your words, it's hard to see what their value could be. I'd like to suggest that this isn't the best way to look at the matter. After all, why are activities that produce tangible results (making shoes, or painting pictures, or building houses) valuable? The plausible answer is that they contribute in some way or another to human welfare, happiness, or flourishing. Some things we need for basic survival - food for example. But a flourishing life calls for a lot more than mere survival. And if something is a reliable source of otherwise harmless pleasure, that pretty clearly gives it value. I suggest that this gives us at least part of the answer to your question. Playing sports gives many people a great deal of...