regulation is a good idea in theory, if only those who created the regulations a) understood every in and out of the sector they were regulating, b) understood the exact pros and cons of the effects of the proposed regulations, c) were... unable to be affected in any way by outside (moneyed) influence and were unable to hide behind the walls of the state, etc, then it might work great. the problem, though, is that regulation has been "weighed in the balances and found wanting". it almost always has the inverse effect of the well-intended solution it is perceived as.
regulation in the economic sector usually solidifies monopolies. they are corporate monopolies, and there are usually 2 or 3 dominant corporations in the sector so as to give the illusion of choice. this is why many (actually, probably most) times, corporations themselves are behind the regulations; it gives big money unfair advantages backed by violence. if Perdue or Tyson want to limit competition, they get a law passed that all chickens have to go through a laundry list of cost-prohibitive "sanitation" exercises, mountains of paperwork, expensive industrial licenses, etc. this has the effect of walling off any free marketeers (little guys) that might be able to come in and undercut the big boys. of course, Big Chicken itself is never held accountable to those regulations. and of course, without the regulations, the people themselves could vote with their dollar; if Little Guy Chickens makes a great product, it competes with Big Chicken and the people win.
you can eliminate lobbying, but there's still going to be the buddy system. Citi asks Smith to put X restriction on banking, and 4 years later, Smith becomes the CEO of Citi and reaps the reward. the fact is, regulations on ANY (non-criminal) actions in the economic sector do not work better than regulation by us little guys via the dollar, and in fact usually work against him.
now, talking about the possibilities in the absence of regulations is where it gets most interesting IMO. there is an important distinction to be made here between regulations and laws (the words can be used interchangeably, but ...I'll draw a hard line for the sake of discussion). laws establish principles like "it's illegal to hurt an innocent people". regulations, well, regulate the way business is done. I certainly agree that the former is necessary and required. the latter, though, I am asserting is better left to the "market", or the people.
now, companies can lie in advertising, but the greatest agent of regulation in a free market - their competitors - will call them out and ruin their reputation (except they can't do this as it is due to FCC regulations). they can lie about what they sell you and whether it's dangerous, but they will be taken to court, sued out of existence, and imprisoned for life for fraud (violation of implicit contract) and injury - this of course only possible without the government status/protection of "corporations".
companies can build crappy buildings, but they will be liable for injuries and will have a crappy reputation to go with it, so it is in their best interest to build a good product.
companies can intentionally make crappy/faulty cars, but without their limited liabilities, the same things will happen to them. the principles above hold true over and over again. however, when the state creates regulations that only ten people can die per million cars sold, then the corporation aims for that number instead of 0, and their actions are legitimized.
the central theme in all I'm saying, of course, is that the state (via regulations) provides protection for the rich in almost everything it does.