City retailers tend to overestimate the importance of parking to their business. They fail to see the many downsides of free parking (congestion and low shopper turnover, among them). They believe more people arrive at the store by car than actually do. They may not even realize that while driving customers spend more per visit, non-drivers spend as much or more in the long term.
And yet whenever a city considers installing a bike lane, rest assured some retailers will protest the perceived loss of automobile access. Take the bike lane that stole a dozen parking spaces from 65th Street in Seattle a couple years back (for reasons that will seem far less arbitrary in a moment). The typical comment from a bike lane opponent to the city's department of transportation went something like this:
Please do not take away the 65th St. traffic lanes for bicycle lanes. Traffic is congested already and eliminating street parking for cars will [be] detrimental for all small businesses located on 65th.
If you find such claims strong on emotion and light on empiricism, you're not alone. Kyle Rowe, who's studying the built environment at the University of Washington, decided to put that standard retail response to the test. He put together a case study to see whether businesses really had a beef with bike lanes, or were making a fuss about nothing [PDF; via Transportation Issues Daily].
Rowe collected city data on taxable retail sales in the corridor before and after the bike lane on 65th Street went into place. He compared the 65th Street sales figures to those generated by a similar retail corridor where no changes had been made to the street, and also to the sales made by retailers in the entire neighborhood. What he found isn't exactly subtle (the green bar is when the lane was installed):