1. It's Alex, not Graham on the Crowbar.
2. When you hit things with the crowbar, it does not move enough for you to notice, but the crowbar will bend slightly. The high-speed shows that.
3. The reason why the Salt broke and the Pepper didn't was because of logical transfer of kinetic energy to potential energy. The salt shaker was a little under full, and so the kinetic energy broke the bottle at the point of least resistance: the neck. Pepper has a natural "springy" property as well (it's more like a leaf than an actual mineral). It was full, so the kinetic energy was transferred into the pepper where it distributed through the entire mineral. Since it was full, there was no place of "least resistance". If they removed about 1/4 of the pepper, it probably would have broken like the salt, since the "non-packing" of the pepper would have not allowed the transfer of kinetic energy into the pepper; it would have shattered the glass.