Maizy stays on leash. When hiking, it is because she is a weird mix of aggressive and friendly (i.e., "Leave my humans alone, but please pet me!") There are people who are afraid of all dogs or unfamiliar dogs, so when we meet other hikers we step off the trail and I let them see I'm holding her so they can pass without discomfort if they want. At the same time, I'm training her to be a lot calmer when we meet new people. I'm seeing slow but sure success.
When we're stopped it is because she likes to roam a bit, and I don't want her getting into some kind of a jam or failing to return. I have a short, light cable I take along which I use to keep her in our camp area. I take her on leash to do her business away from camp, trail, and water, just like at home.
I get very annoyed when an overly friendly or aggressive dog is barking or jumping on me and the owner is weakly yelling at the dog and saying "he doesn't normally do this!" Yes, he does normally do this, and you very well know it; you should either train him not to or restrain him. I like dogs, so I expect a lot from their owners.
"Stand in the ways and see, and ask for the old paths, where the good way is, and walk in it; then you will find rest for your souls."