How does Pa's discussion with man in the black hat exemplify the growing labor problem?

The rumors that the police were going to break up the dance reached the camp. According to Ezra Huston, the chairman of the Central Committee, this is a frequent tactic that the police use. Huston tells Willie Eaton, the head of the entertainment committee, that if he must hit a deputy, do so where they won't bleed. The camp members say that the Californians hate them because the migrants might draw relief without paying income tax, but they refute this, claiming that they pay sales tax and tobacco tax.