Interesting discussion, folks.
Another point we haven't covered is that the change in pitch towards the end of the airfoil, called washout, is also used to reduce the angle of attack in the outboard portion of a fixed wing in order to create a portion of the wing less-likely to stall. This feature helps to resist the likelyhood of stall-spin entry.
Rotorcraft use a simple, straight wing section on the tail rotor as it's purpose is to counter torque, and as we vary the torque applied to the airframe we have to vary the thrust created by our anti-torque rotor without changing the rotational velocity of the wing. This we do by changing the pitch of the blades collectively over a range from slightly negative to very positive, so a simple airfoil is both cheaper and more predictable in performance.
In the case of the main rotor blade, G-Man points out that we can increase VNE using washout to decrease angle of attack at the tip, but we also use the negative angle of attack that results when the collective is bottomed to provide the driving zone during autorotative flight.
The BERP tip is the rotorcraft world's answer to the swept wing on transonic fixed wing aircraft, allowing higher advancing blade tip speed without the undesirable compressibility effects on a straight airfoil. The tip shape also has other beneficial effects in delaying retreating blade stall, which also helps to increase the VNE: at 228mph the BERP-equipped Lynx is the fastest rotorcraft on the planet.