I'm another one who just isn't that excited by travel. I once worked with a woman who, when we were discussing the furthest place we'd travelled to and I said I'd never been outside Europe, looked at me like I'd just crawled off the bottom of a pond. In my head, I snapped back, "Oh, and you're so special because you managed to buy a plane ticket?" Travel is the socially acceptable face of consumerism these days, and like the OP I often wonder what's so wrong with these people's homes that they can't enjoy themselves there. (Humour intended!)
The problem with travel is that it isn't difficult or impressive these days. Spending six weeks travelling on a stage across the country fighting off bandits does not compare to hopping on a plane. Bargaining with savages in the jungle is not the same as wandering round a bazaar talking in English about the nice carpets.
The two things I can kind of understand are exploring natural wonders and visiting people who live somewhere, because then you do really get local culture (but often of the "yes, we buy our food from the supermarket here too" variety.)
Also, I don't think "I don't eat meat or have children so I'm *allowed* to fly" is reasonable. I mean, I don't have a car so does that mean I'm "allowed" to eat as much meat as I want? We don't get allocated however many tons of carbon at birth and get to make trade offs when we spend them. The optimal carbon emissions is 0. Obviously there is a necessary level (fires for warmth) to stay alive, but anything above that is bad, whether you "trade in" bad habits for good ones for not. (I speak as a sinner, not a saint!)
