Once given the option, people choose this form of organization because of it's superiority.
I would be wary of so quickly buying into LLC as only being laws 'permitting' it and having 'superiority'. If a law was passed giving particular companies subsidies of billions of dollars, you might not be surprised if the companies did well and proved their 'superiority', but you would be a little nonplussed at people describing the subsidies as 'permitted'.
As I understand it, LLCs are not so much permitted as subsidized: if you wanted to form a corporation or partnership before various countries fully legalized them, you certainly could, you were indeed 'permitted' to form corporations; what you got, however, was also full liability - the people who made up the corporation were liable for its actions. LLCs get a subsidy in shareholders being able to shed liability and risk for their actions beyond the net worth of the LLC. This is not a free lunch, however, and it comes at the expense of everyone who has a claim against an LLC and discovers it's bankrupt or a shell and that they can't pierce the corporate veil.
Limited liability is not a free lunch. Being able to be sued is an important right - it gives others the confidence to deal with you, as you can be held accountable. Being able to discharge those obligations in bankruptcy means a LLC has to prove its reliability in other ways - for example, by holding more capital, or posting collateral, or simply offering better prices to make up for it. As it happened, this proved to be more efficient that unlimited personal liability, so LLC's won out. Third parties could freely choose to deal with non-LLCs if they want...
-- Mark Friedenbach
Of course, with the prompting to state my own thoughts, I simply had to go and start typing them out. The following contains obvious traces of my own political leanings and philosophy (in short summary: if "Cthulhu only swims left", then I AM CTHULHU... at least until someone explains to me what a Great Old One is doing out of R'lyeh and in West Coast-flavored American politics), but those traces should be taken as evidence of what I believe rather than statements about it.
Because what I was actually trying to talk about, is rationality in politics. Because in fact, while it is hard, while it is spiders, all the normal techniques work on it. There is only one real Cardinal Sin of Attempting to be Rational in Politics, and it is the following argument, stated in generic form that I might capture it from the ether and bury it: "You only believe what you believe for political reasons!" It does not matter if those "reasons" are signaling, privilege, hegemony, or having an invisible devil on your shoulder whispering into your bloody ear: to impugn someone else's epistemology entirely at the meta-level without saying a thing against their object-level claims is anti-epistemology.
Now, on to the ranting! The following are more-or-less a semi-random collection of tips I vomited out for trying to deal with politics rationally. I hope they help. This is a Discussion post because Mark said that might be a good idea.