I regularly toe my brake pads. My bikes all have cantilever brakes -- either the traditional center pull or the newer linear pull. There always seems to be at least just a tiny bit of wiggle in the arms on the post mounts, and I've usually found the need to toe the pads (to mitigate noise). I have also come to prefer the soft and progressive feel of toed brake blocks (vs. ones that firmly contact the rim squarely).