webpack allows some pretty sophisticated resource pipelines that go beyond what you can do with browserify, especially around binary resources.

One of my use cases is working on a HTML5 game. I pre-process all the tilemap levels to add unique IDs to the entities within the file, but only for those JSON files that look like tilemaps. Each of those files' names get mangled as a hash of their contents as well, so I get some cache-busting for free.

Similarly, I can pngcrush the image assets that pass a certain rule, etc.