I recall working on a green at Glencoe Golf Club in 1974 and almost getting hit. Ball whizzed right under my chin and I didn't hear fore, but then again, a player came up and I was doing something and didn't pay attention either.
And there are the occaisional tasks that demand you stay in the line of play. One woman fell in the pond over reaching for golf ball. When I stopped laughing I started trying to get her out of there which took a while and I couldn't let go because she was panicking. The next group played from the tee just over a hundred yards away, so I hoped for the best.
Currently, I am often amazed when riding a course with the superintendent just how oblivious some can be around golfers, and I am often scared to death. I think its a case of familiarity breeds complacency for some. They have driven around so long without getting hit they think they won't be.