Absolutely. In addition to startups, I've worked with quite a few small-to-medium sized agencies, and as you say, they tend to have a small but manageable amount of Dilbertiness.
As I see it, the crucial difference between Dilbert and non-Dilbert is responsiveness to unhappiness and the ability to learn from failure.
In Dilbert-land, an entire engineering department can grow to be silently miserable. Outside of Dilbert-land, many people would raise their voices and with enough protest, major change would happen. That's because management knows that bad morale is deadly, and can't afford to restaff after mass departures. And outside Dilbert-land, people tend to not see themselves as trapped, and really will, indeed, quit.
Also, medium-sized agencies simply cannot afford to have more than 10% of their projects utterly fail - their cash-flow is too limited, and they live on their reputation and good relationships with clients. Unlike the Dilberts, they simply can't walk straight into failure over and over.
