"I've lived a lot of places in the US, and everywhere I've been, they add flouride to the water if it isn't naturally occuring." Your spelling shows that you have most definitely been drinking fluoride for awhile! 
How many communities did you live in that had naturally occurring fluoride already in the water that they ALSO added unnaturally made fluoride to the water supply? The Elwha river that PA sources its water from has naturally occurring fluoride in it and we don't need add it!