Talking with Simon Egli this week, he made an interesting point: Type design is about making forms for other people to use. This is unlike general graphic design, which feel odd when re-used, re-purposed. People feel upset at such plagiarism. But type is made to be re-used and re-purposed. So its natural to desire freedom to go further, and modify the type too. This is part of what motivated me to work on libre fonts for the last 5 years.