I don't consider myself "paranoid." And I do not feel like I sacrifice anything. I do not fear being in public or anything else. But I have always been more comfortable sitting near a wall where I can see a crowd, I've never like huge crowds of people where personal space seems invaded and I've always been quick to notice something suspicious.
These passive "personality traits" have helped me avoid two potentially dangerous situations. One incident happened years ago in Chicago when I noticed a group of "youths" noticing my small group (4 of us) exit a restaurant downtown late at night. They were a block and a half away and it was late. Our vehicle was parked about two blocks away from the restaurant and a block away from the group of suspicious "youths." We immediately altered our route back to the car and when two of the young men started our way, we had the women walk back towards the restaurant and told them we (the guys) would bring the car to them. The two youths followed us to the car and asked for some money in a rather intimidating fashion. They were abruptly persuaded to turn around and rejoin their group now only a block away and we peacefully drove over and picked up the girls.
It was a nonevent as they did "ask" for some money and did not "demand" it. But I believe my awareness and healthy suspicion avoided an actual robbery or worse as we were able to formulate a plan.
For the record, I have noticed other events that turned out to be innocuous. But it's not paranoia. I consider it "street smarts."
Being aware of one’s surroundings, particularly in an urban area, is always a smart move