Is management an inferior degree?

Why would economics be preferred by employers? It's an academic subject, not a professional field. Unless the job was working as an economist or an economic policy role in e.g. the civil service, NGOs, central banks or similar, it makes no difference because outside of those most of the degree is not directly applicable anyway. So it's no better or worse than any other course.

That said I always felt that people who did a management degree as an undergrad only did so as they lacked the imagination to study anything else.

Since employers actually don't in general care what you study, someone who did an intellectually stimulating course in e.g. marine biology, Egyptology, anthropology, languages, nuclear technology etc, will be just as well qualified as anyone else for the generalist grad roles the majority of grads apply to, but will have actually gained something from their years of study beyond just a piece of paper saying they're qualified to do a job.

To each their own though.