The main reason is that throughout Asia – and in too many other places – gambling is illegal. And – given that people will gamble whether it’s illegal or not – that means the punting business is run by criminals. Which of course in nothing new – ask ‘Shoeless Joe’ Jackson!
If you ban something that people want to do, you hand it over to criminals for them to run. And, given that those criminals are (ipso facto) unregulated, the result is the fix – the criminals set up the system to increase their advantage. Forget about the bank having advantage – this is the bank ensuring it wins.
For the sake of sport – and for the liberty of snails climbing up walls or droplets running down windows – we need gambling to be legalised. Only then can we have any chance of controlling the corruption of sport by the bookies and the sharks.