Ah, but imagine it wasn't. Wouldn't it be awesome if rituals had specific requirements and you were only limited by your ability to find someone/something to teach you the ritual and meet its pre-requisites? You could restrict Raise Dead and such to Cleric/Paladin and those devoutly religious, as well as throwing in a monetary cost, time needed, number of people needed and so forth. But something like scrying, perhaps anyone could find out how to do that and with the right time/money/items pull it off. Teleport too, might require a specially prepared area/token item and thus reduce sudden-attack-syndrome, but learnable by anyone with the right abilities/feats - Int for instance so that Wizards find it easy to qualify. Lots of possibilities!