The best word for this movie was "tawdry". Which is exactly what the director was going for. It's a tawdry movie about a tawdry time about a tawdry subculture involved in a tawdry business.
I don't think there was a single character with a 3 digit IQ. This is not to say they were stupid dumb. This wasn't in the "Dumb & Dumber" genre. They were just, well, not really bright, in an average below average way, trying to get by on talents other than mental.