These are the trolleys people (who do not have piped water) use to transport water from the nearest community tap or broken pipeline. Each of them can hold enough pots for one family's daily need.
People in other cities use such trolleys too. Especially Bangalore. The difference is in the diameter of the wheels of the trolley. Bangalore trolleys have large bicycle tyres to navigate the dug up roads. In Bangalore, they are pushed, here they are pulled. Thankfully Mumbai roads and pavements are smoother.