A young boy plays with the contents of a pantry and a cash register, pretending he runs a grocery store.
A young boy is playing with flour and sugar bags.
Playing with the contents of a pantry does not necessarily imply playing with flour and sugar bags.
We have no idea he is playing with flour and sugar bags, he could be playing with anything.
A young boy pretending to be a grocer may not be playing with flour and sugar bags.