Without necessarily disagreeing with your point, it's interesting to note that software developers bear almost zero liability in practice for all the buggy software they write, while even big name law firms get sued, and lose, regularly on malpractice claims. If Microsoft was as "protected" from malpractice as lawyers are, they would've been sued out of existence for Windows 95/98/ME.
The core problem here is the legal system allowing software companies to successfully disclaim all liability for their software products. Traditional manufacturers can and do get sued over defects in their products.
One of the benefits of being unprofessional, I guess, is that the products of our labor are generally considered products of the corporation we work for rather than us as individuals.
Google, SAP, etc, get sued for things like breach of contract, patent infringement, etc. A lawyer or doctor can get sued for his or her work not meeting the expected standard. Imagine the following bug: a variable can take on values of RED, GREEN, and BLUE. You write a switch statement that fails to consider BLUE. Your product crashes, causing your user $5 million in business losses. You get sued for software malpractice, for failure to consider an obvious alternative case.
Well I wasn't really suggesting it as a good thing necessarily. I like the spirit that ethical/competency self-regulation instills in the legal profession, but I'm not sure whether the ultimate market impact is a good thing or not. On one hand, I think the financial industry has suffered from a lack of such regulation (e.g. Goldman advising clients to buy certain products while taking an adverse position themselves). On the other hand, the potential liability and need for insurance creates barriers to entry, driving up prices. Given the staggering potential losses from software, professional malpractice insurance probably wouldn't be cheap. But on the third, alien, hand, I think licensure also has a downward effect on the cost of legal services, by making lawyers more fungible than they would otherwise be (in the absence of licensure, the market might come to rely on an even rarer signal of credibility).
The economic dynamics of licensed professions are a bit more complex than either side of the "developers should be professionals" debate really appreciates.
