Agree that heavy braking, hot brake rotors into cold water, and all that can cause warping...happens to me on and off all the time...Unless they are a hard braker (waits until the last minute to brake for stop signs etc, thus routinely overheating the pads and rotors) another big culprit could be over-tightened wheels.
This is why I stay on top of the guys/gals at the tire shop when I have a rotation or buy new tires. If they go crazy with the impact wrench and over-torque the lugs, that too can warp rotors. I personally "request" that they not use an impact wrench at all, and instead hand tighten them flush and finish them off with a TQ wrench set to the proper torque strength. Since my current tire shop is also the primary sponsor of my late model race car, they usually do it for me at no extra charge and with a smile. (They give me a break on pricing, but since they pay to be on my race car, none of my work there is "free".)
The rotors on my Tundra stay warped, I have them turned every time I rotate anymore, but it's because I tow a couple of heavy trailers (my race car, for one) and overheat them too regularly. But I know it, and I pay for it, no one else to blame but me. I recently bought a new trailer, with trailer brakes, and it seems to be helping this situation greatly.
