[DanielN]

If writing tests for your code is difficult and takes too much time, that is a pretty strong code smell that you're writing unmaintainable code or you are working within an unmaintainable system.

As to the OP's question, the only reasonable scenarios for not writing tests are weekend project style web apps and projects coming out of ad agency style shops where the lifetime of a given project is so short and rushed it doesn't matter whether the code base is maintainable.

The vast majority of places I've talked to in the valley, from three man startups to 100 developer shops, have reported some respectable level of code coverage. It is my opinion that you can read something significant into what is expected of your work and the priorities of the company based on their testing policies.