Spell components generally come in two varieties:
1) Components that exist solely for the sake of flavor
2) Components that are intended to balance a spell with some kind of significant cost (often a significant gp cost)
Unless I'm running a setting where I care about the flavor, I ignore the first type and only care about the second type. For example, right now I'm running my group through PotA in FR. I haven't been using the flavor components. However, I am transitioning the group from FR to my homebrew setting of Tenesia. As part of that transition, I will be implementing the flavor components.
One of the huge flavor components my players may run into is that human(oid) sacrifice is required to bring back the dead. The gods jealously guard the souls they collect, and if you want one back you have to give one in return. And it can't just be any soul. If the gods don't approve of the trade, you aren't getting the soul you want in return. But, you might get an entirely different soul. Consequently, attempts to raise the dead often require sacrificing virgins or the incredibly pious.