Agreed. But you have great water.
Those, like me, whose tap water has high bicarbonate (and alkalinity) concentrations would likely notice significant pH issues with sparging (or even steeping, if using extract+grains), i.e., pH rising. Results in crappy tasting beer.
Kirk, you have to know your water profile and figure out what will work for you. FWIW, you'll notice less pH increase during sparging if you're using RO, distilled, or "spring water". I prefer to build from scratch using RO water and brew salt additions.
You can predict the effect of all this by using Martin's Bru'n water calculator.