I live on Maui. I feel as if it is really difficult to search for tourists when they go missing here because you don't get the same sort of response from the community as you do when the missing person is local. When tourists go missing, it's almost an assumption that they deserved to go missing because they were doing something or going somewhere they shouldn't have. I am not saying this is the case or this is how I feel personally but it is a very common attitude here. Are any of his family or friends able to travel to Kauai to help search efforts? I hate to say it, but without anyone from his circle on island pushing for search efforts, I don't see much effort being put into finding him especially when they aren't entirely sure where to look besides his potential itinerary. I currently have friends form Maui hiking on Kauai and have forwarded them Samuel's picture and itinerary.
The Big Save grocery store in Eleele is quite small and there really isn't much around it. I used to live in the neighboring town of Hanapepe and Big Save was our nearest grocery store. It's all a pretty quiet and rural area. There is a boat launch area just down the street from Big Save (which is located in a small shopping plaza with a few other shops) and I believe there are a lot of boat tours that depart from that marina (Port Allen) that go along the Napali Coast.
