Nothing wrong with Building Societies but you have made a number of factual errors.

Banks try to make money by gambling on the stock market. The Northern Rock bank gambled 75% of its customers money – the average building society has 30% invested in the stock market

a) banks dont make (much) money 'gambling on the stock market' b) N Rock did not gamble 75% of its customers money. It has a very different problem. It lent money long term - on mortgages and borrowed in the short term money markets. When concerns started about its business model it could not borrow any more money. very different problem. The average BS does not have 30% of their money on the stock market.

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