I find it very disgusting! Like said about, they target only ordinary, or underprivilleged people. Why don't they enter in some private properties, and film/record bad actions of the "elite" or real criminals to diffuse it on the internet instead?
Because, they are cowards!
Moreover, this practice is very common in Anglo-Saxon countries, not in Continental Europe, thankfully we do not have such "traditions" to humiliate ordinary/underprivilleged people in a croud, or all over the world on the internet.
Quite the countrary, in Poland, a few years ago some workers of a fancy restaurant did record the Polish "elite" where a lot of them were meeting, big "businessmen" bribing politicians, speaking of the "disgusting Poles and Poland", committing crimes, and diffuse it latter on the internet and it was on TV/radio as well, used in courts, etc. No need to mention, it made a big scandal in the public.
Furthermore, in many continental European countries it is illegal to film/record someone in public and/or diffuse his face/voice without his consent. Of course, you can film someone committing a crime and give it latter to the police, per example, but you can't diffuse it publicly/on the internet (you can however cloud his face, in most case). Making such "traps" is also illegal. I find these laws very senseful.
But, in a few countries if you use a recording/video as an "evidence" of a crime/misdemeanor without the consent of the person in question, in a private space/property, like recording an abusive person, boss, people bribing, comitting crimes, it's irrecevable in a court of law. This is utterly stupid.