They went to America to 'Americanize' their names. Chu became Chuck, Hu became Huck and Bu became Buck.
Su and Fu were denied visas because they had committed tax fraud.
Anti-humor is a type of indirect humor that involves the joke-teller delivering something which is deliberately not funny, or lacking in intrinsic meaning. The practice relies on the expectation on the part of the audience of something humorous, and when this does not happen, the irony itself is of comedic value.