Rick said at 8th min mark that we have to deal with the event on the animation because like that is the asset pack. If you duplicate the animation then you can edit it (add or remove keys or events in this case).
While this is true, it’s often simpler to work within the constraints provided by an asset pack. The full Explosive asset pack has over 1000 animations in it, all using Hit and Shoot events in them. That’s more time than I ever want to spend changing events.
I would like to add, that in the latest version of unity, i was able to rename shoot from the provided animation, didnt have to duplicate. but like Brian said, if i had to do that for 1000 animations id just use the provided events.
You can add events to an animation by selecting the imported model, clicking the Animation tab in the import settings panel, finding the list of animations and selecting the one you want to modify (not from the dropdown, that would map one clip to another, but from the list of clips above it), and then you can open the “events” drawer below and add an event to whatever frame you like. You have to scrub to the right frame in the preview panel at the bottom.
This is my preferred way of adding Animation Events.