it's an order of magnitude easier to replace a single politician with someone who'll vote for laws with teeth than it is to expect [the voluntary market forces to work]
In theory, I could agree with the above. In practice, the politicians in the US are bought and paid for, largely with corporate money. (How else does one explain the DMCA?) Laws on the books, with teeth or otherwise, are no guarantee against wrongdoing by companies - see the ongoing ForclosureGate crap as an example of fraud and felonies of all stripes, with nary a cop in sight.
To the extent that US commerce remains free and voluntary, customers made aware of undesirable business practices divert their business away from the company in question to one extent or another. Absent government-granted and enforced monopolies, competitors will spring up to capture the alienated customers' business.
History is replete with examples of government's failure to replace free markets with government control/regulation.