Another difference, of course, is that when you casually walk into a frat house, there is no contract between you and the frat. There is an appropriate time to discover a cultural mismatch: the job interview. Once there is an employment contract, the law is involved and the law in this country is rather precise about what may not constitute part of your workplace culture.

I have never worked at a company in which the workplace culture really achieved anything like the kind of professionalism my peers in other fields seem to have, but that's irrelevant to the law. If your workplace is perceived hostile, the onus is on the employer to fix it, or face legal repercussions. If you and your two friends form a startup and make life hard on your first employee, that means you--there is no "oh, but if you're a software startup, then your culture is more important" clause.

I think we should endeavor to appreciate the broadness of this protection rather than complain about having to grow up just because in our particular industry, we haven't had to yet. If you still need an outlet for your "culture," form a private club (analogous to a frat) and invite your buddies from work, but keep it out of the workplace.