The addition of some part of the word "economics" to the name of a sport, or sport itself, is possibly a follow on from Freakonomics. Soccernomics takes the last six letters from "economics" and adds it to soccer. Sportonomic$ used the last seven letters and changes the s to a $. GAAconomics uses all but the "e".
One wonders if it was the success of Freakonomics, or the bad press economics got during the Great Recession, that seemed to have people steering clear of using the word "economics" by itself. Stefan Szymanski titled his introduction to the economics of sport as Playbooks and Checkbooks (although "economics" does make it to the subtitle). Beautiful Game Theory and Circus Maximus also have "economics" in the subtitle. The word does not feature anywhere in Scorecasting: The Hidden Influence Behind How Sports and Played and Games Are Won. Then again, it could be argued that it is a book more driven by finance and psychology rather than economics. Stephen Dobson and John Goddard did use "economics" in the title of their book The Economics of Football but this book was first published in 2001.
"Economics" does show up in the textbooks, e.g. Sports Economics by Rodney Fort and The Economics of Sport by Michael Leeds and Peter von Allmen. One could argue that these textbooks have their roots in books that did not use the word economics in the title. Rather, one was more likely to find "business" in the title. For example, over two decades ago James Quirk and Rodney Fort published Pay Dirt: The Business of Professional Team Sports. A further two decades before that there was Roger Noll's edited volume Government and the Sports Business.