对于“商用”的理解，我个人认为是修改开源软件并售卖或付费分发开源软件。如果这么理解，那么根据gnu.org上，对 Free software (不是open source software，但free software是包含于OSS的) 的定义：

“Free software” means software that respects users' freedom and community ... Thus, “free software” is a matter of liberty, not price. ... We sometimes call it “libre software,” borrowing the French or Spanish word for “free” as in freedom, to show we do not mean the software is gratis.

You may have paid money to get copies of a free program, or you may have obtained copies at no charge. But regardless of how you got your copies, you always have the freedom to copy and change the software, even to sell copies.

同时，另一篇文章Selling Free Software中也提到：

Actually, we encourage people who redistribute free software to charge as much as they wish or can. If a license does not permit users to make copies and sell them, it is a nonfree license.

这说明，free software或者开源软件并不限制软件的售卖，同时后文也提到，nonfree software即使以低价甚至免费分发，也不能使它们成为free software。

当然，我是支持开源的。我个人比较喜欢MIT、CC0，即几乎不限制任何行为，随使用者喜好。