I find these practices ridiculous. Sure their money is on the line, but if you have no red flags on someone besides their industry I think you should stand by your commitments. If someone starts falling late on payments and can't explain why that will correct in the short-term that is a different matter.
I think there is going to be a real market for a credit card company that sets really high initial standards but isn't finicky about the market as a whole and thus doesn't arbitrarily go after its own prime customers. These business owners are the real money makers for these guys because of the money they put through their cards every year and if a company can cater to these businesses with excellent payment histories then they will make the profits that Amex is turning away.
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