Maybe if you had bottled water, you'd drink it instead of coke and other nasty things.
Despite popular belief, tap water, even with a Britta, is nothing like bottled water which is actually nice to drink.
In many cases, bottled water is coming from a municipal water source. It's treated and filtered the same way all municipal water is. About the only thing that happens is that the companies sometimes re-introduce minerals to enhance the flavor.