It is not unusual to see surfboards in Tamarindo, as there are a lot of people who walk around town with their surfboards on their way to and from the beach. If a store wants to get drop in traffic from surfers, why not provide a little parking area for surfers, bicycles, and surfers on bicycles?
It must be a little tricky to ride a bicycle while carrying a surfboard, however. When I was in junior high school in St. Louis County, Missouri, I used to ride to school on my bicycle while carrying a trombone in its case in one arm. A surfboard is a lot bigger than a trombone case, however, and it does not have a handle. But, I guess if someone is agile enough to surf and ride the waves, they have the coordination to be able to ride a bicycle while carrying a surfboard.