It is leeching, though. Those people who do not swap gear and are instead providing minimal effort towards others are leeching. A DD among "equals" (I'm talking non-empy versus non-empy or empy vs empy) who provides less than 1% of the parse is leeching. A mage who can't help cure, or has all their nukes resisted, or can't land an enfeeble on a mob that's not immune is a leech. Maybe it's not in the typical "I'm sitting there doing nothing" style, but it's still leeching. You can "try" all you want, but if you're accomplishing nothing, you might as well be doing nothing.