**SOLVED** Why does globally installed gem/script fail when run in a directory with a Gemfile?

gistfile1.txt

tamara@pontiki:~/a/b/c/d/e/f:2014-03-27@07:55:24
$ mkdir test_dir

tamara@pontiki:~/a/b/c/d/e/f:2014-03-27@07:55:31
$ pushd test_dir/
~/a/b/c/d/e/f/test_dir ~/a/b/c/d/e/f ~

tamara@pontiki:~/a/b/c/d/e/f/test_dir:2014-03-27@07:55:43
$ gem env
RubyGems Environment:
  - RUBYGEMS VERSION: 2.0.14
  - RUBY VERSION: 2.0.0 (2013-11-22 patchlevel 353) [x86_64-darwin13.0.0]
  - INSTALLATION DIRECTORY: /Users/tamara/.gem/ruby/2.0.0
  - RUBY EXECUTABLE: /opt/rubies/ruby-2.0.0-p353/bin/ruby
  - EXECUTABLE DIRECTORY: /Users/tamara/.gem/ruby/2.0.0/bin
  - RUBYGEMS PLATFORMS:
    - ruby
    - x86_64-darwin-13
  - GEM PATHS:
     - /Users/tamara/.gem/ruby/2.0.0
     - /opt/rubies/ruby-2.0.0-p353/lib/ruby/gems/2.0.0
  - GEM CONFIGURATION:
     - :update_sources => true
     - :verbose => true
     - :backtrace => false
     - :bulk_threshold => 1000
     - "install" => "--no-wrappers --no-document"
  - REMOTE SOURCES:
     - https://rubygems.org/

tamara@pontiki:~/a/b/c/d/e/f/test_dir:2014-03-27@07:55:52
$ which rubytapas
/opt/rubies/ruby-2.0.0-p353/bin/rubytapas

tamara@pontiki:~/a/b/c/d/e/f/test_dir:2014-03-27@07:55:56
$ rubytapas
Commands:
  rubytapas all             # Download all rubytapas episodes
  rubytapas download        # Downloads the listed episode's files into a new directory with the episode tag in the given directory
  rubytapas help [COMMAND]  # Describe available commands or one specific command


tamara@pontiki:~/a/b/c/d/e/f/test_dir:2014-03-27@07:56:04
$ touch Gemfile

tamara@pontiki:~/a/b/c/d/e/f/test_dir:2014-03-27@07:56:08
$ rubytapas
/opt/rubies/ruby-2.0.0-p353/bin/rubytapas:4:in `require': cannot load such file -- thor (LoadError)
	from /opt/rubies/ruby-2.0.0-p353/bin/rubytapas:4:in `<main>'

tamara@pontiki:~/a/b/c/d/e/f/test_dir:2014-03-27@07:56:12
$ gem env
RubyGems Environment:
  - RUBYGEMS VERSION: 2.0.14
  - RUBY VERSION: 2.0.0 (2013-11-22 patchlevel 353) [x86_64-darwin13.0.0]
  - INSTALLATION DIRECTORY: /Users/tamara/.gem/ruby/2.0.0
  - RUBY EXECUTABLE: /opt/rubies/ruby-2.0.0-p353/bin/ruby
  - EXECUTABLE DIRECTORY: /Users/tamara/.gem/ruby/2.0.0/bin
  - RUBYGEMS PLATFORMS:
    - ruby
    - x86_64-darwin-13
  - GEM PATHS:
     - /Users/tamara/.gem/ruby/2.0.0
     - /opt/rubies/ruby-2.0.0-p353/lib/ruby/gems/2.0.0
  - GEM CONFIGURATION:
     - :update_sources => true
     - :verbose => true
     - :backtrace => false
     - :bulk_threshold => 1000
     - "install" => "--no-wrappers --no-document"
  - REMOTE SOURCES:
     - https://rubygems.org/

tamara@pontiki:~/a/b/c/d/e/f/test_dir:2014-03-27@07:57:34
$ 

Because at the top of the executable scripts I had:

require 'rubygems'
require 'bundler/setup'

so it was doing exactly what I told it to. Just not what I wanted it to.