Why don't more projects use Ruby Symbols instead of Strings?

Question

When I first started reading about and learning ruby, I read something about the power of ruby symbols over strings: symbols are stored in memory only once, while strings ar

Answer 1

One reason for the usage of strings may be the usage of yaml to define the values.

require 'yaml'
data = YAML.load(<<-data
    one:
      title: one
      tag: 1
    two:
      title: two
      tag: 2
  data
  )  #-> {"one"=>{"title"=>"one", "tag"=>1}, "two"=>{"title"=>"two", "tag"=>2}}

You may use yaml to define symbol-keys:

require 'yaml'
data = YAML.load(<<-data
    :one:
      :title: one
      :tag: 1
    :two:
      :title: two
      :tag: 2
  data
  ) #-> {:one=>{:title=>"one", :tag=>1}, :two=>{:title=>"two", :tag=>2}}

But in the yaml-definition symbols look a bit strange, strings looks more natural.

Another reason for strings as keys: Depending on the use case, it can be reasonable to sort by keys, but you can't sort symbols (at least not without a conversion to strings).