I agree that some of the folklore built up around "hackers" is a bunch of bullshit, but I disagree with some of your assertions. I would never work for a company with a dress code of business casual. It's not that I want to wear comfortable clothes at work (business casual is perfectly comfortable, it just looks horrible), it's that I think dress codes of any kind for most non-client-facing white collar workers are a sign of superficiality and ridiculous control issues on the part of the employer.

I'm also not sure that hacking is "just a job." For some companies and some people it is, but I've done my best to avoid working for anyone that thinks like that. I believe hacking is a creative endeavor, and in general I don't believe any creative person wants to be beholden to capricious and arbitrary rules surrounding their manner of dress. That's an absurd use of authority.