I know we have it in a couple of places, but the one I just found is All The Tropes:Trope Namer Syndrome (which isn't the one I wanted to find, which I just saw a few days ago, of course). In short, the idea was to forestall naming tropes after specific instances from existing works (like "The Spock") on the grounds of Small Reference Pools. This obviously doesn't apply to "The Gambling Addict", but I see nothing about the definitive article in that trope name that offers any advantage over just calling it "Gambling Addict".
-- Bob
I have been Roland, Beowulf, Achilles, Gilgamesh, Clark Kent, Mary Sue, DJ Croft, Skysaber. I have been
called a hundred names and will be called a thousand more before the sun grows dim and cold....
I have been Roland, Beowulf, Achilles, Gilgamesh, Clark Kent, Mary Sue, DJ Croft, Skysaber. I have been
called a hundred names and will be called a thousand more before the sun grows dim and cold....