I don't see the elderly Mr. Dashwood as Scrooge. Scrooge had no good intentions (at the beginning of the book) for anyone other than himself. I see Mr. Dashwood as kindly and well-meant, but things not working out as he intended. He left all the children (granddaughters and great-grandson) something that he felt would be useful. I'm sure, as others have said, he never thought that Mr. Dashwood would die so quickly, he didn't after all. Perhaps he assumed that a good constitution ran in the family! He knew he was a good man with money and he ran under the assumption that he would manage the property well and have more money to add to the girls' funds when he finally passed away. The older two granddaughters were getting to marriagable age - I'm sure he thought they would be married while their father was still alive and in charge of the estate. He fell in love with his great-grandson and wanted (in my opinion) to make sure the estate went down the Dashwood line.