Australia has a population 1/4 the size of Great Britain and has sports teams that effectively match per capital those teams. But I'm just going to focus on the Australian Teams.
It's fair to say that countries choose sporting competitions with the goal to make results realisable and the competition fair. So starting with the sport that has very little going for it in Australia or New Zealand. Football (soccer please). The A League has a cap of 10 teams, 9 in Australia and 1 in NZ. You'd think with the growing player base and better Asia/Oceania competition they would foster more than 10. Not so. Seems their population demographics say they would ruin the competition if they increased. So 10 teams it will remain.
Ergo the Australian NBL competition, they too have done there homework. An 8 team competition is just the ticket, given in their case the lack of sponsorship/team ownership. Outside of the USA basketball is a boutique sport.
Starting to see a pattern here. Teams that play the round ball code struggle and the oval Ball codes rule.
Ok so we now pass onto the only game in Australia that doesn't have a World Cup. As Baseball is to America, AFL is to Aussie. Chalk and cheese. By far he biggest competition in Australia with 18 teams with 18 players per game, AFL is a huge player base to draw from (1,400,000 Wiki) The fact that AFL survives is down to the longevity and popularity of the sport. And marketing. Other sports in the same city centres struggle to get local athletes to their sport.
Equally as popular in all regions barring West Australia and Northern Territories, is the NRL. The National Rugby League has 16 teams and many outside the original hotbed of the game, Sydney. The sport has gone through some massive changes in the near past but seems settled now. And it is a fluid competition with sometimes one or two teams continually at the top. Probably fair to say the game in Australia has similarities to AFL as far as competition and coverage
And then there is the Super 18 rugby teams, five in number and getting worse as time goes by. Plainly put, Australian rugby is in dire need of a return to the good days. Numbers to the game are shrinking and with that shrinking the $$$$ are simply drying up. With better placed teams in AFL and NRL the Rugby $$$ and player base are diminishing.
And money needs to be pumped into the game but that "Old" money is gone.
And simply put, there is only so much money and resources across all sports to be had.
