A devout N=1 guy here, so my costs per mile fall with every ride. This year, I've already gone through 7 tires, 3 chains, 1 cassette, an FD, a set of jockey wheels, and two sets of brake pads-- but that's pretty much it. I'm around +/- $700 worth of consumables, but just passed 9,000 miles for the year, so call it 7¢ a mile? I know that folks who do a lot of organized rides/events can have fees blow away consumables and even bike cost in just a couple of years.