Why does Rails 5 edge version API-only app includes Sprockets and SAAS in Gemfile?

Question

I have generated a skeleton-API-only app based on Rails 5 edge version using command:

  rails app_name --api --edge

Its Gemfile includes Sprockets and SASS gems as can be seen in it.

gem 'sprockets-rails', github: "rails/sprockets-rails"
gem 'sprockets', github: "rails/sprockets"
gem 'sass-rails', github: "rails/sass-rails"

I was just wondering what purpose Sprockets and SASS should serve in an API-only app? Is it purposely done or by the time Rails 5 is officially released this should be fixed.

I also observed that when generated the Rails app the generator did created the assets folder, however removed it later as can be seen in the output shown below:

  create  app
  create  app/assets/config/manifest.js
  create  app/assets/javascripts/application.js
  create  app/assets/stylesheets/application.css
  create  app/controllers/application_controller.rb
  create  app/helpers/application_helper.rb
  create  app/jobs/application_job.rb
  create  app/views/layouts/application.html.erb
  create  app/assets/images/.keep
  create  app/mailers/.keep
  create  app/models/.keep
  create  app/controllers/concerns/.keep
  create  app/models/concerns/.keep
  create  bin
  create  bin/bundle
  create  bin/rails
  create  bin/rake
  create  bin/setup
  create  bin/update
  create  config
  create  config/routes.rb
  create  config/application.rb
  create  config/environment.rb
  create  config/secrets.yml
  create  config/environments
  create  config/environments/development.rb
  create  config/environments/production.rb
  create  config/environments/test.rb
  create  config/initializers
  create  config/initializers/active_record_belongs_to_required_by_default.rb
  create  config/initializers/application_controller_renderer.rb
  create  config/initializers/assets.rb
  create  config/initializers/backtrace_silencers.rb
  create  config/initializers/callback_terminator.rb
  create  config/initializers/cookies_serializer.rb
  create  config/initializers/cors.rb
  create  config/initializers/filter_parameter_logging.rb
  create  config/initializers/inflections.rb
  create  config/initializers/mime_types.rb
  create  config/initializers/session_store.rb
  create  config/initializers/wrap_parameters.rb
  create  config/locales
  create  config/locales/en.yml
  create  config/boot.rb
  create  config/database.yml
  create  db
  create  db/seeds.rb
  create  lib
  create  lib/tasks
  create  lib/tasks/.keep
  create  lib/assets
  create  lib/assets/.keep
  create  log
  create  log/.keep
  create  public
  create  public/404.html
  create  public/422.html
  create  public/500.html
  create  public/favicon.ico
  create  public/robots.txt
  create  test/fixtures
  create  test/fixtures/.keep
  create  test/fixtures/files
  create  test/fixtures/files/.keep
  create  test/controllers
  create  test/controllers/.keep
  create  test/mailers
  create  test/mailers/.keep
  create  test/models
  create  test/models/.keep
  create  test/helpers
  create  test/helpers/.keep
  create  test/integration
  create  test/integration/.keep
  create  test/test_helper.rb
  create  tmp
  create  tmp/.keep
  create  tmp/cache
  create  tmp/cache/assets
  create  vendor/assets/stylesheets
  create  vendor/assets/stylesheets/.keep
  remove  app/assets
  remove  lib/assets
  remove  tmp/cache/assets
  remove  vendor/assets
  remove  app/helpers
  remove  test/helpers
  remove  app/views
  remove  app/assets/javascripts
  remove  config/initializers/assets.rb
  remove  config/initializers/session_store.rb
  remove  config/initializers/cookies_serializer.rb
     run  bundle install

Thanks.