Mike getting beat up

That scene always stuck with me.
It's not as if Jim could have stepped in single-handedly and saved the day....but surely he could have rounded up a few fairground workers and came to his friends aid?
I know it's merely a plot device to highlight how much of a selfish bastard Jim was.....but all the same it struck me as odd.

It's weird, because it's always scenes like this one (in primarily 'British' movies) that stick with me, long after the movie has ended (think Dennis Waterman in 'FRIGHT'......or Ray Winstone in 'QUADROPHENIA')