When I tell people I’m a scuba instructor...most of the time, they can’t believe there are places around suitable for diving. It tell them about a few places around Houston and their eyes light up. Their typical response is.."you mean there’s a clear lake around here" OR "you can scuba dive in that river"?
Dive centers with a store front should consider showing off photos of their local dive sites with big, colorful, glossy, poster boards. Maybe rent a billboard in town, and instead of listing your company logo and name alone...show a great photo of a clear lake or river near you to grab someone’s attention. I bet you could even get the dive site to pay for part of the in-store photo or billboard ad.
If a person walks by your store and sees a big picture of a wonderful looking dive site with a caption that says "only 20 minutes from here" ...they may be more apt to inquire about diving or snorkeling lessons. Most non-divers that are land locked assume scuba diving is for vacation only. Show them it doesn’t have to be.