It bears consideration that different people eat differently. You and I, for instance. From the OP I gather that you watch not only what you eat, but also the amount. I, on the other hand, eat as much as I want of whatever I want. I would eat this way whether I rode or not, so riding or not riding doesn't save me any money. Riding does, however, keep me from getting fat.

I don't eat more just because I rode a longer distance.

Likewise, longer distance does not generate more laundry for someone like me. I don't stop mid-ride to change clothes. I may stop and add or remove a layer for weather related reasons, but that is rare. Usually if I wear it to ride to work, I put it on again to ride home; again, with consideration to the weather conditions.

The only reason I see to choose driving the car over a bike is time constraints.

So I don't look at bike commuting as saving any money from those points of view. I do see bike commuting as saving me all the money associated with owning a second car.