It definitely makes the situation feel a lot lower pressure to me. After all, the chief activity is taking a hike/walk, so if the conversation lulls it never feels awkward and there's always something new to see and remark on.
I had a manager who (back when we were office workers) liked to do outdoor walking 1-on-1 meetings. TBH, I really disliked it, but not enough to ask to stay indoors. I found the noise and sights rather distracting.
It's true, but in a busy city environment, you're pretty much forced to form pairs. Because of the noise, it's very hard to hear what the person on the other side is saying.