"We often hear that a driver 'lost control' and caused an accident. This kind of bland reporting should be followed by a little 'oops' as they all make it sound so innocent. I'm sorry, drivers don't lose control, they give it up. Either they're going too fast for conditions, get distracted by a shiny object, or simply run out of talent. Cars rarely spin out of control of their own volition." (David S. Wallens, Grassroots Motorsports magazine, August 2007, p34.)

No offense but it sounds like your friends brought those messes on themselves. And these events are perfectly safe if you drive smartly. That is, within YOUR limits. Although I will say... if you don't have some fear... and a healthy respect for the learning process... and the ability to put your ego aside... and the ability to accept instruction... and a concept of "volume knob, not light switch"... DO NOT sign up for these events.