Building more road capacity is a fool's errand. Ultimately, investing in efficient mass transit and encouraging biking and (gasp!) walking is much less expensive than slapping down more asphalt. And of course, cars have all sorts of hidden costs to society, like pollution, that don't factor into your thinking. How much busier would the streets be if the 6% of bike commuters drove to work instead? It's just silly to rant against the costs of painting a bike lane while ignoring the many benefits.