That's what Georgetown law prof. Anne Fleming has to say in her Washington Post op-ed Federal regulation of payday loans is actually a win for states’ rights. It includes this defense of federal regulation:
Critics of the CFPB rule, such as House Financial Services Committee Chairman Jeb Hensarling (R-Tex.), argue that federal regulation of these loans infringes on state sovereignty. But the current system of state-level regulation, without any federal floor, imposes its burdens on states that seek to protect their residents from payday loans. Lenders often operate across state lines, lending from states where payday loans are permitted to borrowers in states where such loans are illegal. This makes it incredibly difficult for these “restrictive” states to protect their residents from being saddled with unaffordable debts.