Ohio Open (Gun) Carry Laws

Tonight I went into a local grocery store in a relatively good mood. My workday was over and the weather was exceeding warm for February, in the sixties. I went in the neighborhood grocery store to pick up a couple things we needed for the evening, milk, ketchup, etc.
My mood quickly changed when I noticed a younger, bit overweight man browsing an isle. He was in jeans and a sweatshirt, no sign of any kind of uniform or marking on his chest. I was watching him because I noticed what was on his belt. At first I thought it may be some other kind of device, because I was looking at three clips. But as I saw his other side, I saw the handgun on his right. He as walking slowly away from me and I just stopped and stared, without realizing what I was doing. When he got out of sight and checked out I resumed getting the groceries I came for, but in a much different mood. I found myself inspecting everyone around me much more carefully, looking around isles before stepping out. I was feeling fear, fear of other humans.
I have to ask, how is it that people feel safer this way? It has never made me feel safer to see ordinary citizens with guns, only more fearful.
Ohio is and has been very liberal in its gun laws; practically anyone can carry a gun almost anywhere, except in places with alcohol, and there is some restrictions in motor vehicles. Below are some relevant links:
General Info
Carry permits
Possession of firearm in beer liquor permit premises
Firearms in a motor vehicle
State preemption of local laws