We've seen this happen with system fonts as well, apps sometimes bundle the San Francisco font with an app instead of relying on a system font. There may be some reasons to include the font or sound file, such as if it changes in different versions of the OS. Of course that would make the app inconsistent with the rest of the OS, which may not be the best behavior. We discuss some other tradeoffs with bundling these system resources on our blog post which covers the Spark app: https://www.emergetools.com/blog/posts/7AppsThatCouldSaveYou...