Reading the opening of the Law chapter i find myself thinking that local politicians may have quietly welcomed the Shiawasa decision. Once a corporation claims extraterritoriality, that is a area of the city that they no longer have to budget for. And i suspect the corporations are still paying some kind of tax or rent on their property. Sure, various regulations on emissions and such may be moot, but the politicians can point to the extraterritoriality and claim it is out of their hands. End result, less ground to cover by city services, perhaps less cases to prosecute (as long as they happen on corp turf, the city rent-a-cops don't care), and so on.
Hell, it may explain why runners can operate even in SR4's data sphere. Get onto corp grounds using an assumed id and such, keep the demolition to within corp borders, slip into the surrounding city and the rent-a-cops will just shrug unless the corp representative can slap some kind of id and extradition request on the desk. It is basically not their problem, and why should they inconvenience one of their citizens over some corporate allegation? In particular if the corporation is unwilling to say exactly why (black project snatch and grab, gotta love em) they want this citizen extradited?