Wrapping coils is easy, it only takes a few minutes. If you have a jig or coiling tool like the Kuro Coiler or Coil-Master, then it gets even easier. Now, getting them mounted, wicked, and working properly could be a different story but like all things, practice makes perfect. I'm no pro, by any means, but I bet I could install a fresh coil before you could get to the store and back with a new one.
It's not necessarily about the cost, because you're right that I'm just going to spend that money on something else anyway. It is disposable income, after all. But what I spend it on, doesn't necessarily have to be disposable. I'd just spend it on something that I'll get to keep around and enjoy for a while, rather than something I'm just going to throw out in a week. Plus, there's the whole issue of availability. What are you going to do a year from now, when the manufacturer stops producing your favorite coils for your favorite tank? What about in two years, when the FDA pulls everything but the BT cig-a-likes off the market? Me, I'll just wrap up a new one like I been doing. As you said yourself, to each his own, but even if you prefer the factory coils, and continue to use them as long as they're available, having a nice rebuildable, and the skills and materials to make it work right, could be a handy "insurance policy" to have in case the worst does eventually happen.
Same goes for mech mods. You might not prefer them, they might not be your "style." But everybody should at least have one, learn how to use it safely, and then even if you shove it in a box in the back of your closet and forget about it, you'll still have something functional once your last regulated mod kicks the bucket and you can't buy new ones anymore thanks to FDA's "regulations."
