Merching screws up the economy really bad. And when an item is being merched such as the Leaf-Bladed sword it won't sell in the GE.
And I don't get why you quit after the release of dungoneering it's a skill that doesn't require anything, nor do you have to spend money to train it, and furthermore you don't even have to do it.
I am an average player, with not a lot of wealth or any stuff like that. I'm, what, level 81, and I have like spare 2m.
I'm not obsessed with it, in fact, I'm close to being completely done with the game. This means if I do get on again, training/whatever will be >2 hours.
I was looking forward to a new way to train. I got a new way to just mess around, which is cool, but not at all what I wanted.
And time is just as valuable as money.
I have a feeling your answer will be "just don't play it then," and that is what I have done.