Standing outside with placards barely gets any coverage and certainly no consideration from MPs we all know that. There's a reason there's a long standing tradition of shouting at MPs in transit as they'll usually get aired.
I don't recall many being outraged with the abuse Farage, Cameron or Boris got and that was often at their homes. There's an obvious double standard its either right or wrong not just when the person is deemed to have deserved it.
Personally i think if its people going in to parliament, a place of work, or a televised event then fine, if its whilst they're living their life off camera then that's a totally seperate issue.