TherealLogros wrote:
If you define it that way, I'd say every way in which you upgrade your character is a perk you get for completing a certain task. Many of which give an achievement as well. Level to 85 as a really trivial example.
Reputation grinds existed way before achievements. So, clinging to your example, you don't get a perk for the achievement. You complete a certain task and get your reward. And you also get the achievement. And that's not what the OP meant. If I understood correctly.
If you think about it, though, I think what's being said is that while the achievement itself isn't offering a reward, that which offered the achievement does offer one, so effectively it's as though the achievement gave said reward.
The real pickle is deciding which achievements should offer rewards if you look at it that way. They should likely be achievements that make sense and possibly even give meaningful rewards, but at the same time they can't be of a nature that they'd become required beyond what's already required by the community.
And ultimately, aside from perhaps things like rep gain percentage increases or reduction in costs of buying things from vendors, I really can't see any meaningful achievement rewards not becoming required by the community as a pre-req for joining their groups or whatnot.