I'm not familiar with Locomotive but I would say that most of the time getting my environment working had to do with installing other technologies like resque, mysql, mongo, heroku, gems (devise,haml,aws-ses,rspec,cucumber,pdfkit,js-routes), etc.

I'm guessing the majority of people don't spend the majority of their time installing rails. It's all the other requirements that are needed to build out the application.