I'm not a copyright expert, but I believe that several years ago congress passed a law that a typeface (usable as a font) cannot be copyrighted to prevent use in print, but it can be protected against unauthorized distribution.
I've always thought the "free for personal use" is vague. Maybe someone can clarify...If I print T-shirts for my family reunion, that's personal use? But if I get paid to print T-shirts for someone else's family reunion that's commercial use? But the product is the same either way...
Now that we are in the digital age, it's becoming nearly impossible to prevent intellectual property from being distributed without authorization. In the old days you had to physically purchase a "font" in one form or another (film negative, metal slugs, linotype mold, etc.) but now that they are electronic one can make unlimited copies for free, The same is true for sound recordings, e-books and everything else. It may not be right, especially from the point of view of the font designers, musicians, and authors, but it is the reality of the modern age.