A little old, but here are some internal use cases for GWT at Google: https://groups.google.com/forum/m/?fromgroups#!topic/google-...

I don't think it comes down to not liking JS. JS has its uses, but you get quickly diminishing productivity returns as your application gets larger and hairier. I've actually had a project where the "M" and the "C" (of MVC) was written in GWT-able Java, and the view with JS. Right tool for each job.