We wanted to be able in the future to be able to automatically add / append the license text to the file. Adding the licenses one by one would be tedious so coming up with a way to bulk add the licenses seems essential.
Also, some of my open source projects have an explicit clause which states that 'The source of this code shall not be misrepresented' so if chunks of my code showed up in some AI-generated code without attribution, it would be a pretty clear-cut case.