The percentages don't greatly surprise me. I am a little surprised that many permit holders don't/won't regularly carry? I have always had the philosophy that it is "better to have and not need, than to need and not have" - including auto seat belts and airbags, motorcycle helmets, and a means to defend myself.
Studies have consistently shown permissive carry states consistently show decreases in violent crime rates even with a relatively small percentage of concealed permits (and apparently even fewer holders actually carrying). It raises the odds that the bad guys will run into an armed potental victim, and they can't predict who is armed.