First off, never believe everything you read or hear.
Second, these two sentences are quite different--
"A South Korean man died after a marathon session playing computer games."
"A South Korean man died because of a marathon session playing computer
games."
Since the statement that you reported was the first one, then I'm not
greatly surprised. When you die, you had to have been doing something
before your demise. This guy just happened to be playing computer games.
That is no different than--
"I young Turk dies after drinking a cup of coffee."
For some reason, most might assume that because one event follows the other
that there must be a cause-effect relationship. Obviously, this is not
always the case.
:)
Alanb