I replaced rvm with rbenv on my Macbook and after doing so I've needed to add require 'rubygems'
to things to get them working.
Is there a way of forcing rubygems to be required, or removing the need for it?
For sanity reasons you should always require what you need. As rubygems is included by default in ruby 1.9 you should do something like:
require 'rubygems' unless defined?(Gem)
at the top of your script.