I've noticed in my years of playing WoW that hunters tend to lean more toward solitude than groups. Part of this is due to our incredible soloing abilities as a class, but I wonder if part of this drive to wander off alone with our pets stems from our own personalities.
Don't get me wrong, I enjoy grouping with others - I doubt I could stand to play a healer otherwise. But I go through bouts of wanderlust, where I just want to go off alone with my pets and just do quiet things, like fish or farm. Since I can't gather on Kalliope anymore, I occasionally do this on gatherer alts, like my druid or rogue, but the habit started on Kalli. I don't tend to sit around and stare into space in scenic areas on other classes either, even if I stay mounted and technically don't have my pet "with" me. I'd say it was due to Kalli being my main, but my alt hunters get some of this sort of time as well.
The funny thing is that there are plenty of other classes that are self-sufficient, but plenty of hunters are just drawn to that class in particular. Ease of play might be it for some. Love of pets might drive others. And for a small group of us, well....we just vant to be alone.