Lobbying for laws that restrict the sale of a good or service to consumers typically comes from a combination of do-gooders (paternalists who think the item is bad for consumers) and rent-seekers (business owners who will profit from the restriction). Bruce Yandle famously labeled the coalition that favors restriction of legal alcohol sales “Baptists and bootleggers”.

Here’s another example, from today’s St. Louis Post-Dispatch:

Money lending by so-called "payday" stores, often found outside military bases, is drawing increasing national attention - and appears headed for a showdown in Washington.

Citing "predatory" lending practices, Sen. Jim Talent, R-Mo., has guided a bill through the Senate that would cap the annual percentage rate of loans to military personnel at 36 percent. … Rep. Sam Graves, R-Mo., earlier filed legislation identical to Talent's …

The “predatory lending” label – as though lenders were kidnapping soldiers and forcing them to sign loan contracts – reflects the do-gooder perspective. The rent-seeking perspective comes to light later in the article:

Talent's chief opponent in the fall's Senate race, Missouri Auditor Claire McCaskill, said the bills by Graves and Talent were crafted to avoid affecting Pioneer Financial Services, a firm based in Kansas City that makes longer-term loans to service members and that has contributed to Graves. [A payday lender trade association] said the bill would help Pioneer by killing its payday competitors.

Recommended reading: Jeremy Bentham, Defence of Usury.