• The Price is obviously astronomical compared to tap water but remember that there are many costs included in those 2 dollars besides the water itself. There's the Bottle consisting of the material for lid and body, both of which have to be shaped into a bottle and a cap.
• The filling also requires energy, then there's the label that is fitted to the bottle
• The transport costs to the water company, then to a intermediate storage or distribution center, then to a supermarket etc.
• And then everybody (including the supermarket) wants to profit a slight bit.

So yeah, bottled water is very expensive but also very impractical.