What it sounds like people are talking about in here is shock value (Whether in a conversation or a production of media or whatever). It's a tactic used by people to quickly draw someone's attention, to wave a red flag so people will remember their action. They use bad taste to compensate for a lack of more socially appropriate skills used to draw people's attention, such as the abilities to express concern, wit, intellect, elegance, strength, and talent. Bad taste is more socially acceptable nowadays, probably due to more advanced media outlets over the last few decades, particularly the internet, where the most obscene of materials is accessible in an instant. It affects society as a whole at the subconscious level, perhaps in a similar way excessive advertising does.