Continuity mistake: In the beach chase scene, the sun is on the right side of the truck, in the next shot the truck goes flying off a pier with the sun on the left side of the truck.
Continuity mistake: During Motormouth's fight with the two punks watch closely. One moment the grocer's sitting on the back of his truck, his arms on his lap. The very next shot they're suddenly crossed.
Answer: First: they threw the first punches, which Jones blocked. Second: they were criminals assaulting a member of the public. Third: they continued attacking him, so he continued to fight them.
Greg Dwyer