I asked some friends of mine who have a lot more river running experience than I if they had ever have felt threatened by other folks while they were on float trips. They said that they learned early on to not camp near any river-side towns. Their bad experience occurred at Bluff, Utah while running the San Juan. They were awakened one night, by drunk locals going through their stuff. The situation was diffused, when the intruders were given several cans of beer each and they wandered off into the dark. Could it have turned nasty? Possibly.......