Actually a lot of judges would consider a stranger suddenly approaching you and screaming in your face a threatening act.
Isn’t something like this considered creating a disturbance on private property? It certainly is every place I’ve been. I probably would have told those people to leave-with a heavy implement like a hammer in one hand, and invited the angry customers to help me out-a restaurant is not public property that you can protest on.
Disorderly conduct should be the charge. The usual MSM suspects “out to brunch” on this.