Take a look at my Profile for some Eligibility jokes.
some interesting notes in there.
for more clarity, I wonder if it would be at all possible to look at participation of active players and the percentages of those players on WGT countries of origin.
the numbers could potentially be skewed in regards to worlds population and even the US population because the entire country is not wired or connected or have the luxury of playing a video game.
I suspect that scenario increases in other countries that may have even less access to a full range of public utilities like running water, let alone a home computer or mobile phone.
None of this dismisses your larger concern or references to some of the games best not even being eligible or included in certain events. That too even skews potentially who some consider some of the games best because some just don't participate or are excluded because they are not considered eligible.