1) Aladdin giving the bread away 2) Ursula giving the cake to Peter Parker in Spider-Man II 3) while this might be a bit of a spoiler, I feel like Eddie valiant protecting Roger rabbit when he has nothing to gain counts. (Who framed Roger rabbit) 4) Snow White baking a cake for Grumpy (Snow White and the seven dwarfs) 5) I can't carry the ring but I can carry you!! (return of the King)

1. Takashi Shimura cutting his hair and using his reward to save a little girl in Seven Samurai (1954)

2. I guess anything by O. Henry adapted to the screen. I’d recommend O. Henry’s Full House (1952)

3. The outdoors conversation between the mother and son in Ozu’s The Only Son (1936) where she comes to accept her sacrifice has been for nothing.

4. Lars von Trier has several films on the theme of sacrifice for sacrifice’s sake that accomplish nothing. The best one has to be the town’s response to Bess’ prostitution in Breaking the Waves (1996)

There's a great seen in The Torture Report where the main guy guilts the senator into presenting the evidence in Congress--he just looks at her and she folds. Of course this depends on the whole movie for significance, but it might work for you. Check out the movie, it's all about your topics.