I'm fairly sure near to all publishers require display of their name in the publisher field (which is how they would have grabbed this datum). It's essentially free marketing, how 'games from this publisher' are linked, publisher stores are displayed, and so on. And getting elitist over the GDC of all things is pretty darn funny! Be sure to also get the latest news from Gamasutra and get into that hardcore coding at Flipcode.
Term used by _whom_? Because nobody at DICE or GDC talks like that -- just peanut gallery blogs.
"And it turns out that it's the overwhelming majority of games."
Overwhelming majority... _of the way games are marketed_, not the reality of production. It's called "print the legend."