Code Warriors - people who believe in the superiority and righteousness of their chosen sport and who believe they are entitled to things they arent - like the name of the game for instance. Soccer didnt decide that football only meant one thing, they decided that their games name in Australia should fall in line with what is probaly the name of the most popular game in the world, english or not.
At which point the differentiation is between whether its the game of Australian Football, or the game of Football in Australia.
I pretty much figure that its people over-reacting to a simple name change that didnt otherwise alter anything in the Australian sporting landscape and most of whom have no goodwill for soccer, whatever it calls itself.
I didnt particularly care either way, i thought it was a mistake for soccer to do so at the time from a business perspective, and still do, given we have 4 codes of football here that are high profile (AFL, Soccer, Union and league) as well as other lower profile variants (Grid Iron, Gaelic).
& the same in the US ...