I'm sorry that your father's family grew up on the border between needing charity and giving it (that's always hard). But have you considered that maybe they c

I'm sorry that your father's family grew up on the border between needing charity and giving it (that's always hard). But have you considered that maybe they chose to give 10% because they had discerned they could make do with the 90% that was left and they wanted to bestow charity like the widow with two mites? Simple is not foolish, though it may appear so. Your dad may not have understood what their thought process was, though he could see what appeared to be coercive external pressures. (That which is coerced is not charity and if that was going on it should have been stopped.)