Sequoia National Park does not require bear canisters. I was just there a few days ago. There were quite a number of steel bear lockers scattered out along the trail where I went.
Incidentally, as I was driving into the park very early on Sunday morning, an injured black bear was limping across the road. I slowed down even more to look, and the poor creature was carrying its left hind paw two or three inches above the ground. Once it got to the shoulder of the road and my car was there, it looked at me so woefully like it really deserved a food handout. Well, of course, I was not going to feed it anything, and I did not want to get it habituated to human food. However, if ever an animal deserved a little help, that would have been the one. It may have been injured jumping off someplace where it wasn't supposed to be.
I must have a warm spot in my heart for bears.