Also consider: you should be getting a couple of hours of cardio a week anyway. You'd have to do that laundry.
I don't spend squat on my bike anymore, after the first couple of years. Chains, brake pads, tires. I did have a broken axle this year, so that cost me $100, and I picked up a spare helmet and a couple of other things, so $80 there, and new studded tires for $130, but that should be it for several years. On an average year I spend < $100, and if I for some reason can't ride, I use the treadmill or something else and have to wash just as much stuff.

Plus, I'm on a well, so washing doesn't really cost me much, I'm not paying much for water.

But honestly, I'd still ride even if cars and gas were free. I'm not doing this to save money.