That argument seems to prove too much? It's sort of an Efficient Market Hypothesis for government regulation, and it would apply just as much to e.g. FTC and DoJ with respect to anti-trust violations as to Congress (as thread parent would like) or DoJ or whomever with respect to fraud or illegal wiretapping. Maybe it would be better investigated by a class-action plaintiffs' attorney, but even the mightiest firms might hesitate to wage the discovery battle that would be required against such deep pockets.