It can't be said enough. Safety and common sense are a must, or we will all be effected. What most people don't think about is that the media does not look for what happens often and the norm. They get more by showing the rare and bazar. In the minds of the public if a scuba diver dies, they think "that has happened before, so what?" However, if a person in a tail dies, that is media gold. Think about it. If you turned on the TV or logged on to a news site and there was a story that said something along the line of "Mermaid Dead," or "Girl Wearing Mermaid Costume Drowns," would you not stay tuned? Who would not, and could you blame them? It is a very juicy story that will get them a lot of viewers.
For many of these people, this will be their first time hearing of mermaiding as a hobby and possibly even swimming using the dolphin kick. A lot of people, as you probably see from comments on the tail ban stuff, believe that wearing a tail is a handicap. They believe that a person in a tail cannot honestly swim as good as someone without. Even though we all know better and will try to explain that is far from fact, they are emotionally driven. Logic will not convince a great many of them because they still "feel" it is unsafe. Since mermaiding is not something they do, they don't give a (insert word you want here) if it is out lawed. In the 1980's, there was a score of martial art and ninja movies came out. Many Americans and Europeans saw nunchacku and ninja stars for the time, and many got the idea that they were not something that should be legal, despite the fact that these weapons had been available in the west for some time and had never been used in any crime. Most people didn't practice martial arts, let alone with these weapons, so they didn't care if they were banned. To this day they are restricted in many areas.

Don't doubt that the same thing can happen to mermaiding.