It should be noted that Ballmer did attend Harvard so it isn't just some random donation out of the blue.
I've learned over the years that, when a bio says "So-and-so attended Harvard", it means So-and-so went there but didn't finish. Not that I object! Harvard dropouts like Gates, Zuck, and Matt Damon often do exceptionally well—they typically leave because they have an opportunity that's even better than attending Harvard.
I think it's possible to donate to a wide variety of causes - a similar argument cropped up on some of the ESA discussions here yesterday, with some people asking why we should bother spending money in space when there's a lot of pressing problems on earth. Investing in education could result in discoveries being made that could benefit millions of people. We are probably in agreement about buying a basketball team being a waste of money though!
I'm guessing there are even more?
A basketball team is an asset. It's not like he spent the money on blow. It's an investment, just like anything else (although it happens to be one he's passionate about).
But I can't judge him. He isn't trying to be like Bill Gates and that's fine.
That said, it's his money. He can spend as he sees fit and unless he sees clubbing baby seals or something equally morally reprehensible as his aim, who are we to take aim?
http://www.heritage.org/federalbudget/top10-percent-income-e...
Here's another take on U.S. taxation: https://www.americanprogress.org/issues/tax-reform/news/2011...
http://www.facethefactsusa.org/facts/a-tax-impact-from-grand...
I am ready and willing to "take aim" and go even farther to stop someone, if that someone is behaving sufficiently immorally. My threshold for acceptable and unacceptable generally falls on the issue of whether an individual is harming another living thing. Killing to eat is acceptable. Clubbing baby seals because you're a sadistic billionaire is not acceptable.