I added the red wool to help with finding them and it really helped. Even so, I lost two out there which was very annoying. I don't think they added much drag, it's just light wool.
You aren't the first to express concern
You're right though, the camera makes them look a lot closer. No-one was in any danger, even from a ricochet. I've been slinging there a long time now with tennis nalls, stones and now lead and nothing has ever landed anywhere near the path. The angle is very deceptive. I would love to have a more remote area to use, but this is the best I have so I have people walking past occasionally. We're moving actually fairly soon so hopefully I'll find something better. A good slinging spot is top of the list of requirements