I modify my bikes, all of them, to better suit me and the conditions in which I ride.
Most of the additions (or farkles, if you like) are shop made or heavily modified commercially availabe things, because I like making things.
The AM version of this answer is "for the same reason you asked the question. I want to."
"Here is your country. Cherish these natural wonders, cherish the natural resources, cherish the history and romance as a sacred heritage, for your children and your children's children. Do not let selfish men or greedy interests skin your country of its beauty, its riches or its romance.” T.R.