And just to show how retarded the "less marginal utility" argument is, let me propose a hypothetical to BL:
I'll use cars instead of cheeseburgers.
Let's say BL is single, because he can't find a woman who doesn't find him to be a complete moron. Since he doesn't have to worry about a wife or kids, he decides that he is going to collect cars because he really, really likes cars. He's now up to five cars. Now since he can only drive one car at a time, he really only needs one to get to work, or to go to the store to buy cheeseburgers. Car #2 has less marginal utility than car #1, etc. Logic follows that car #5 has the least marginal utility to him.
Moy is BL's neighbor, and he doesn't have a car. Maybe he had one, but it died, and he cannot afford another one. He now has no way to get to work. He can't car pool with BL, because their jobs are in completely different directions.
SInce it's better for society that moy gets to work everyday, since he doesn't want to live off the government teat, does moy have some sort of inherent right to expect that BL's car #5 be taken from BL and given to him, since BL's car #5 has the least marginal utility to him? After all, he still has four other cars and shouldn't miss the fifth one.