It's good to tell people thank you.
John is visiting his grandparents who are hosting him for the weekend.
John wants to ask his grandparents for some financial help.
John helps his grandparents around the house the entire weekend and thanks them for being such gracious hosts before broaching the subject of his financial problems.
john reminds his grandparents of the last time they helped him out and demands more of the same.
John's grandparents give him a talking to about the finances but appreciate what a good grand son he is and ultimately help him out.
John's grandparents see him as ungrateful for the previous help and John does not get the financial help he needs.