Well its not that expensive compared to some other hobbys, for exampel cars, airsoft or overclocking, but i guess everything depends on what level you takes it to. Photography equipment is also a investment though you can sell alot of it to a good price. And i can promise you that most jobs require some super expensive equipment.
It can get very expensive, if you take it beyond a doodling-to-while-away-the-time level. We're not just talking about a #2 pencil and a sheet of typing paper at that point. You'd have sets of drawing pencils, lead holders, mechanical pencils in specific thicknesses, woodless pencils, artist's stumps, kneaded erasers, soft plastic erasers, art gum erasers, special sharpeners, sandpaper blocks for shaping pencil points, rulers, compases, and templates, pads of artist's paper for rough sketches, bristol board pads for finished product, cans of fixative spray to prevent smudging, and so on.
I would think you cant compare hobbies to eachother. For instance, A full frame camera, Plus a set of prime lenses, Plus a set of telephoto lenses (One of Sony's high end lenses is 13,000 usd) With creative lenses like fisheye and wide angle. Plus lights. Plus external flashes. Plus studio space. Plus expenses of traveling for photography reasons.
I would think that'd add up to a lot more than airsoft. But my real question is why do people invest so much in capturing a fraction of a second
I'm a professional musician, and have spent quite a huge load of money to get some decent gear. Then I got into photography, and you'd have to do a similar investment to reach that same level. And that's excluding the cost of training and education if you do that. Most art forms are expensive. Even if you do pencil drawings, you have to spend a lot of time on it. Time equals money after you turn 18.