hehe yeah, the stuff you can find fishing is mostly useless I think, but i remember once some halfling fishing in Hlint reeled in an axe of some sort... -I- was laughing like crazy and at that point I thought he was just making it up. Then he showed it to me. Great RP spawned by a silly addition to the fishing system.
Sand is more of a solitary activity so I'm not sure if it would have the same impact, so this anecdote is probably irrelevant