This thread proves that there are as many definitions of what hardcore really is as there are people. It's basically just a word to boost the self-confidence of the one using it, mostly at the expense of someone else.
Difficulty in gaming has, as proven by frybread, little to do with the hardcore label.
It's more of a question of how accessible a game is. Some people do not put that much energy into really learning the rules of a game. These people usually fall under the 'casual' label and are easilly scared by complexity. Others, the ones we often call hardcore, demand more from the games. Deeper, more difficult, better graphics etc. These people can spend an insane amount of time learning how the game works, and are not discouraged by complexity.
Naturally, there are levels to this as well.
Some people think that a high difficulty is a good thing, and are prepared to spend hours just to beat that one boss. They think this is fun. Some of these people need to confirm that they are better than others because of this and therefore label difficult games hardcore and simple games casual.
"I beat this game! I'm so hardcore!"
One should not bash what others think is fun. They're not bad people for it, and neither are you for disagreeing with them. I mean this in general, and it's not really aimed at anyone.
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