It's a way to pass the time, which is a big problem for us retirees. I envy people like MassiveD, who can find joy passing the hours tying knots. A friend of mine paints. I tried that but it did nothing for me. Another friend finds joy passing the hours in his garden and workshop. Reminds me of the chores I was forced to do as a boy and which I always hated: cutting the grass, raking leaves, painting the porch, etc. Reading (including diddling around on the internet) is good for maybe three hours a day and after that I'm anxious to get out and exercise my body. But running in circles, running on a treadmill, swimming laps, etc are joyless, at least to me. So that's how I got into travel when I first retired about 10 years ago. First hiking city to city in Europe, then wilderness backpacking in the United States, now bike touring in the backcountry of the United States. A way to pass the time pleasantly, while exercising the body in a natural organic way and stimulating the mind with constant novelty.