Barbecuing is an outdoor activity. Some might call it a sport. There are certainly enough competitions that one could easily view it as such. Considering some of the hunks of meat that end up on the grill, it also is not difficult to see barbecuing as being a strenuous activity. Fishing is also said to be a sport (or at least it has its competitive elements). Therefore, it only makes sense to put a grill on a boat.