Why does lena younger oppose her son walter's liquor store scheme?

In _A Raisin in the Sun_ by Lorraine Hansberry, Walter Younger has a plan to open up a liquor store.  Normally, a parent would support a child’s ambitions, but in the instance of Walter Younger this is not the case.  His mother Lena Younger opposes his opening of a liquor store because she is morally opposed to the drinking of alcohol and looks down upon it and what it can lead to.

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