It would be wrong to say that the vouchers take the place of money, for vouchers cannot be easily replaced if lost, and you'd be stuck using your hard-earned money instead. The Disney Dining Plans, offered as upgrades by the Walt Disney Travel Company, are not, to my mind, good values. Interestingly enough, it is very difficult to find solid information about them either in print media or online. I have no doubts that some folks prefer the more structured vacations that arise from vouchers. I prefer the joy of discovery and the freedom to decide where, when, and what to eat next.
Disney vacations are about attractions, yes.
But don't underestimate the joy of good food when you discover it. When you force yourself to eat it for the sake of pre-bought vouchers, you may discover that the bad taste in your mouth is only indirectly related to the food.