Rugby League Night on BBC 4.

Last night was Rugby League night on BBC 4 and fans of the game itself, Eddie Waring or that great movie This Sporting Life must have been in their element. I have never followed rugby of either code that much but the social and political issues reflected in the Union/League schism have always interested me and no prizes for guessing where my sympathies lay. One thing that I have never really understood is why Welsh pitmen stuck to the snooty Union amateur code while their northern counterparts opted for the League and an extra couple of quid on Saturday afternoon. Can anyone explain this to a dim Southerner who lives just down the road from Twickers?