Cars pollute our air, leading to our nation's capital having one of the nation's highest asthma rates, particularly among children. Subsidized space for cars disproportionately benefits those who can afford cars in the first place and probably don't need a handout. And let's not forget that cars hit, in declining level of frequency, people, homes, and Rhodeside Grill.
Bike sharing, on the other hand, leads to zero pollution or childhood asthma, takes up very little space, and is free for the first 30 minutes of each trip (though you do need a credit card to register).
But somehow the Arlington Republican Party thinks cars are more in need of taxpayer support. As Matt Yglesias writes, "It's all just a reminder that sincere devotion to free markets plays almost no role in economic policy debates. It's identity politics all the way down."