One of the problems with working in-house is that in many of these kinds of situations, the company isn't really about design or marketing or publishing or creativity. Instead, in-house groups tend to put together various print and web-related materials that the company knows that it needs but isn't focused on and doesn't really understand. Consequently, the bosses, even the ones over the in-house creative staff, tend to come from the general company culture and don't get the creative thing.
I once had a job for a government agency where I was the equivalent of the creative director. The person just over me, however, was a biologist with a military background. The guy was utterly clueless about anything creative, and worse still, he didn't realize that he was clueless and *** that the entire creative staff was composed of a bunch of arrogant, undisciplined oddballs who didn't know how to follow orders or sit still during his marathon three-day meetings. His sheer incompetence in the job eventually drove most of my creative staff, including me, out of the government agency. He ended up replacing everyone with people like himself who had no formal design/communication education, little worthwhile experience and no aptitude for design, marketing, public relations, videography or writing. He did, however, fit in with the general agency culture and was, consequently, listened to by the agency director who was equally clueless about how creative staffs worked and the skills they possessed.
Every in-house situation is different, however, and my example is just that — my example. There are some commonalities, however, that tend to show up time and time again. For example, the in-house creative staff is often regarded as the equivalent of graphics short-order cooks who stand by to await their design orders from those who request them. Instead of being thought of as creative thinkers and problem solvers, they're regarded as service personnel to implement other people's ideas. After all, intelligence and thinking aren't required to design a logo or a brochure, Photoshop and PowerPoint does it all for you — right?
On the other hand, in-house situations can be great if you land at the right company. In-house jobs sometimes let designers focus on longer-term projects and fine-tune ongoing campaigns and materials to a degree not possible in ad agency environments on fixed budgets and shortened time frames. Really, it all depends. One thing's for sure, though — life is too short to spend 40 hours per week at a job that you hate. If the company isn't a good fit, make the best of it, but actively look for something better and leave as soon as you find it.