"At least someone is making money off the stupid this way"
There are already laws to defend the mentally handicapped aganst sexual exploitation, but raping their wallets is OK in your little world I guess?
The people who go to payday loan companies are mainly desperate, not stupid. They're taking the loan so they can pay the rent or eat. Sure, there will be the odd cretin who goes to Wonga so he can buy a PS4 and those people deserve whatever they get, but in the main payday loan companies are morally equivalent to a man offering a homeless woman a bed for the night if she'll fuck him.