Why you should crush bottle after use.
Travelling by train or bus? In the earlier days, families used to carry lot water from home with them. Now-a-days no body takes that effort. You get to buy water from train and stations. However, you have very high chance of buying chances of buying duplicate product. Take a look at this picture where IRCTC workers are filling bottles with water meant to be used for cleaning train and in toilets.
Before buying water always ensure that seal is intact and the bottle is in good shape.