There is a huge disconnect between american and asian market (mostly indian) when it comes to rates charged by drupal shops, I have not seen indian drupal shops charging over 40-50$/hr however established and number of years they have been in business. North American and European clients usually turn towards India, China to cut their costs and is but obvious that an attempt for straight comparison would be stupid, but even when you talk about proportions the best shops have a difference of over 6 times when it comes to per hr rates (50$/hr in comparison to 300$/hr) 

Why do you feel there is so much difference? Some things that comes to my mind:

1> The perception that going to india/china means multifold cost cutting.

2> Perception (and to some extent the fact) that the efficiency of these shops is much less than that of american/european counterparts (I am actually interested in efficiency aspects and how it affects the rates) 

One of my favorite videos on approach to programming, the notion that there is no silver bullet to programming and there will never be one perfect language for all your needs is the mantra a polyglot lives by. For me a polyglot is an open minded infidel who sees his world beyond hate and security, he is someone who understands that perfection is not achieved by ant like dedication. He bend his tools for the purpose and not the other way round. 

Foy Savas on polyglots unite --- ( There is a much better slide-video sync version at infoq )