Honest Sancho
Ironically, Honest Sancho is a liar with nothing honest about him whatsoever. He misleads his costumers, he mistreats the Mexicans that he pretends are robots. He sells robots like a car salesman, trying to get money for himself. He represents the way that people will sometimes misuse each other to get ahead. 'Sancho' is also Mexican slang for someone you wouldn't trust, like a homewrecker.
The Farm Worker robot
The most commonly purchased Mexican robot is apparently the Farm Worker robot which is a stereotypical symbol for Mexicans who work in fields on crop rotations. This is an essential aspect of the struggle that faces Mexican families, and it shows their willingness to work hard for modest pay. In this case, the robot lampoons this stereotype, so that the robot represents a racist prejudice that some people believe about Mexicans.
Johnny Pachuco as a symbol
Another lampooned stereotype; Johnny Pachuco represents the common prejudice of fear that some people feel toward Mexicans. He is violent and involved in a gang, and he speaks disrespectfully. He is offensive, but at least he speaks English. The last bit is kind of a joke, because it shows that whether someone speaks English or not is absolutely no indication of their criminal life. Johnny is a hysterical depiction of a common fear.
The Mexican/American motif
The dilemma about wanting something Mexican that still has American parts is strangely symbolic, because it shows Mexican culture and identity to be a bad thing, or at least a disappointing thing. The more Mexican, the more one can get from the robot, but if it gets too Mexican, the quality might be poor. The dilemma symbolizes a racist attitude toward Mexico and Mexican people.
The symbol revolution
When the robots come to life chanting "Viva la revolucion!" it symbolizes something. It symbolizes that by pigeon-holing Mexican people into narrow, hateful stereotypes, people make Mexicans into a kind of lower class. The revolution is a symbolic reference to the injustice of racism and xenophobia, because they are invoking Marxist language, basically. The scene is a symbol for social progress and reform.
