I guess you haven’t been to many rallies or protests. People always show up with unrelated issues, and there’s not much you can do about it as an organizer. I helped to organize a protest asking Trump to release his taxes, and people showed up with signs to abolish ICE (immigration enforcement). I went to a rally to get out the vote, and the local congresswoman was drowned out by a woman who wanted her son freed from prison. Politicians will push whatever they think is advantageous to themselves (though the better ones will stay on topic).

Free speech is a wonderful thing, but there can be too much of a good thing. Learning when to shut up can be valuable too, one doesn’t offend people like the parent post.