I see this as a hobby. I've saved up components from other builds and working on bikes or deciding how to build up a bike is a bit of science and art. It fills more than a cycling need for me. My style of cycling is pretty much the same, so that would make all my bikes redundant, but it doesn't matter. I've got different pairs of running shoes, for example. They all serve the same purpose so why have more than one? Technically I don't require that many, but I enjoy variety. I figure, if I've got the money and the space, why not have an interesting and healthy hobby. Sell the bikes after awhile and get different projects.