As someone without a dog in this fight - I'm a bit confused - What do you mean by, they were "looking for people who aren't boycotting Israel?" I haven't seen anything to suggest that's the case. They were canvassing and giving out leaflets from the looks of things.
People are allowed to go door to door political canvassing, even people you don't like.
All I can see in the videos on twitter are a second group of people approaching them, shouting 'Jew hunt' and disrupting whatever it was they were doing, and presumably trying to get a reaction out of them for social media.
The woman clearly initiates the the brief physical interaction, and I haven't seen anybody 'grabbed by the throat' or headbutted.
The man in the glasses clearly states to the woman when questioned that they're canvassing support for Palestine, which they have every right to do. She she asks if they're recording addresses and again, he clearly states that they knock on every door and note the people who don't want to speak to them so they don't bother them again, like anybody going door-to-door does.
To frame that as a 'Jew hunt' or claim that they were 'gathering addresses of people who aren't boycotting Israel' is a gross misrepresentation. The pro-Palestine group were confronted by a second group of people shouting, filming and attempting to move them on and reacted as anyone would.
I'm clearly missing something because people are calling them brown shirts, when anyone with eyes in their head can see who instigated that confrontation. Are there more videos?
I respect the right to counter-protest, but this wasn't a protest, it was doorstep canvassing. I have a very low opinion of groups who to try to outright silence those they disagree with. It makes me wonder what they don't want people to hear.
And turning up mob handed to confront people, then trying to spin it as them being violent towards you, is pathetic behavior.