The difference is the action taken against you. Pushing is not the same thing as shooting at someone with bodyguards. It would all be part of a larger picture of course, but in the scenario of a baseball game, it could very well be argued that the foreseeable consequences for the pusher did not realistically include death, while that could almost never be assumed about a gun. The Baldwin case being a good example of when that argument could be made, as we assume he honestly believed he was holding a sophisticated and professional prop.