Well if you look at a lot of the mainstream MMO's, you'll notice that a lot of them are going away from hardcore gamers and leaving more towards being a casual gamer-friendly environment. This is especially more so or F2P games. Mainly because it's the casual gamers who are addicted enough to the game to spend money but they're also not so addicted that they have no life outside of the game. Most hardcore gamers are hardcore because they can play all day due to lack of school/jobs but since the person only plays all day, they won't have a large source of income to spend towards the game.
Also AFK leeching can be considered a "safer" way of going up to your friend and saying "help me lvl my char. I'll give you my ID/PW and you just afk my char when you lvl and talk on it if the GM shows up". Since DRG allows for legal multi-clienting on 1 computer, it's easy to open multiple clients an just afk chars next to the ones you're actually playing. This way, you get the exp from now playing because a non-afk person is logged on your char which gives almost the same results as if the owner is logged on the char but just afk.
PS: I'm not for nor against AFK leeching. Just helping Cupid with his argument.