YES!! You can go to almost any lake or stream and find empty bottles littering the banks. Even tho they're recyclable, many people don't. If you don't want to drink your tap water, they make refillable pitchers that will filter the water.
It depends on the type of material used to store water. Bottled water products are good if they are sold in PET, a fully recyclable and safe food packaging solution. I believe brands use such type of recyclable materials. So if you consume bottled water, better go with brands or check with the packaging details on the bottle.
Yes they create waste only. There is no authority to regulate the quality of bottled water so filling a water bottle from a tap is just as good, if not better than the bottled water companies. It's cheaper to. Dasani bottled water, bottled by Coke Cola is simply tap water from a city water source and they admit it. Short term exposure to the plastic is no risk.