Tokens don't cost anything? The only fee you pay for is to recharge it, which is very miniscule. Tokens cost quite a lot. The concept of opportunity cost is, quite literally, the first thing they teach you in a basic economics course. (At least, in my state's textbooks it is.) The cost of a Chaotic Shield is, at a minimum, 400k Dungeoneering xp. Would you reduce your level by nearly half a million xp for this shield? Would you trade a Chaotic Rapier for it? Would you trade a bonecrusher, scroll of augury, and arcane stream necklace for it? Because that's what you have to do--you need to choose between the shield and all of those things and more. If you take the shield, you lose out on everything else you could have bought with that 400k--or you do until you make it another third of the way to lv99, anyway. The fact that you don't come out with less cash than you started is irrelevant, as nothing you can possibly do will ever make you come out behind in cash--you start out the game with 0 gp. I can spend 120m on 99 prayer and still come out with no net loss. TL;DR: time is money