Yes this is a useful method, but doesn't work all the time. I've extensively utilized this kind of font piracy and I've been disappointed more often than not, now that my requirements are of more rare fonts. Basically, people add codes and software for free and openly on GitHub. Sometimes, they have specific typeface requirements, so the software company or coder buys the font and attaches it so that the app/software can use the font from there when a user downloads the whole script. You can find a large number of otherwise premium fonts on GitHub, some even come up if you just type fontname.ttf because GitHub will be the only place that has the typeface file (.ttf) and it comes up in Google. Actually this is becoming an issue for programmers who are involuntarily indulging in font piracy using GitHub: https://www.reddit.com/r/programming/comments/735y45/how_github_became_the_webs_largest_font_piracy/.