The reason for minification is not hiding the source code (which is impossible), but to reduce the payload size served to clients. Web pages (even web apps) are documents fully available to clients where users can choose to view, inspect and even modify their source code.
Well, to play devil's advocate, typically only the minified version is exposed.
However I agree that in the end outside of making it more readable, it's not making a huge difference.
The reason for minification is not hiding the source code (which is impossible), but to reduce the payload size served to clients. Web pages (even web apps) are documents fully available to clients where users can choose to view, inspect and even modify their source code.