You don't often think of bottled water along the same lines as smoking, drinking alcohol or gambling. But when it comes to wasting money, it's just as bad a habit. Most people don't consider drinking bottled water a bad habit because they have come to believe that it is healthier for them than tap water. While this may be true in some countries where the water supply is not clean and safe, it isn't true for those living in the U.S. The bottled water you are drinking may come from the same place as the the water you're already paying for. If the package label indicates it is "purified," then chances are it originates from a municipal water supply. PepsiCo ( PEP) recently admitted its Aquafina, the top-selling bottled water sold in the U.S., originates from " public water sources " -- or tap water. The company says it removes chlorides, salts and other substances that can affect a water's taste. Dasani, the second-leading bottled water in the U.S. from Coca-Cola ( KO), also originally comes from public water sources , meaning that at least 24% of bottled water originally comes from good old tap water. Tap water is highly regulated and monitored for quality -- much more so than bottled water. Bottled water can legally contain many more chemicals than tap water because it is regulated by the Food and Drug Administration, as opposed to the Environmental Protection Agency, which regulates tap water.