To be fair, game designers and developers have certainly been asking themselves the question, “How can we keep a 5 hour/week player engaged in a game while the 40+ hour player is running laps around them?”

The venerable UO had the Power Hour, where bonus experience could be earned during set intervals. World of Warcraft provides an experience bonus if your character rests at an inn (the bonus earned when you play the next time). But these don't go far enough.

Here's what I'd like to see: instead of Vanille Ice and all the millions of unused characters sitting on their collective tookuses, why not imagine that each day they venture forth and do some low-level crime fighting (orc slaying, etc.) just to, you know, “stay in shape”. Now this workout wouldn't actually happen in any way visible to players logged on, but these characters would earn nominal amounts of experience each day. And in three months time, presto, a new level.
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