1. a Spanish-American farm labourer or unskilled worker
2. (Historical Terms) (formerly in Spanish America) a debtor compelled to work off his debts
3. any very poor person
Now that Byron is convinced he is a peon, he complains about welfare food, specifically powdered milk and a big block of cheese. Welfare is is not an official name, but it is a term used to describe a United States program started during the Great Depression to provide for families who, for various reasons, are not able to provide for themselves. (Remember what you know about the Great Depression. Why might people have needed help?) One way aid was given was with food.
Powdered milk is created through a process that evaporates the liquid from milk leaving a powder. Water is then added to the powder to make milk. (Powdered milk is a big part of baby formula.)
Cheese was provided in large blocks, but not quite the forty pound loaf Byron mentions.
Kenny and Byron see a bird sitting on a telephone wire. It's described as "about the size of a pigeon and was grayish brown with a long pointy tail hanging underneath it." Byron says, "That's a mourning dove, they're the coolest birds in the world, don't nothing shake them up!"
Finally, Kenny says that if a genie gave him three wishes, he "wouldn't mind using all three of them to wish some real bad stuff on [Byron]." And not stupid things like the fairy tale lady who wished her husband had a sausage on his nose. I didn't know, but that's an actual story, although the husband is the one who wishes the sausage onto his wife's nose.