As @elcapitan said, licensing is the same as for software. Fonts are intellectual property (IP), just like most other intangible products of R&D. It is too bad,

As @elcapitan said, licensing is the same as for software. Fonts are intellectual property (IP), just like most other intangible products of R&D. It is too bad, of course, and my usual opinion about IP applies. However, we don't live in an ideal world, and many of us are stuck following rules we don't agree with. What I'd personally find more interesting is a first-principles research effort to find out what makes some fonts so much better than others. My gut tells me that such an effort might yield, as a side effect, a formal method for creating such fonts that are especially well suited for a specific purpose.