Tennis Popularity Worldwide Distribution

Watching a little of the Abu Dhabi Exhibition and notice it is being played in a half empty stadium. Can't help noting that tournaments in this part of the world despite attracting the top players are often played in cavernous stadiums lacking in atmosphere and with the the sound of play having an unusual echo because of the lack of spectators. The tournaments in China are similar in that they struggle to attract an audience. What a contrast to the exhibitions and tournaments played in South America. The recent exhibitions played by Nadal, Djokovic, Ferrer and Nalbanbdian amongst others were "rocking" and the tournaments played by Nadal at the beginning of the year were similarly well attended.

Maybe Shanghai should be replaced by a Masters in South America?

South America is long due a Masters, as is the grass season.
Tennis/sport in the Middle East has a different dynamic - the Abu Dhabi event is just a cash cow and warm up for the players, the results don't count and the audience knows it.
In terms of popularity, I'd say per capita its Europe > Asia/Australia > South America > North America > Africa/Middle East.