Safety & security are often synonymized in non-computer fields, and to be honest they are similar in many places. Typically, people who need to know the difference, like computer security experts, know the difference, while people who have never tried to secure a system of any type from attack, like regular users (who should still know but often don't) will not know the difference. For another example, from the first comment under this answer, a fire exit would make a building more safe from fires, but less safe from intruders. Occupants of the building typically do not need to know how to do this, as the architect will have done it already.
On the other hand, in some cases these "security experts" will still be making the enclosing more secure, even as they make it safer. They have to do both. For example, a biologist with a specialization in disease would need to make a person more secure from viruses (for example), and this involves plugging up every hole, securing every vector of attack. By definition, this will make the person's body more secure from attack, as well as safer from harm.
It seems more people on Super User are regular users and biologists than we would hope.