Here is an interesting quote from The British Usurpers Carausius & Allectus by P. J. Casey
The numismatist is normally thought of by historians and archaeologists less as a contributor of primary evidence, ideas or historical synthesis and more as a classificatory specialist. A scientist in his own right, the numismatist has been marginalized in the evolution of the explication of the historical process and thus a primary source of information has been largely neglected. (pg 11)
This quote reminded me of my own experiences in grad school working on my master's in history. I tried to explain to some people what I did with ancient coins and then became known to some as the coin collector. I even had to explain to my second reader why I was not just an antiquarian -- the term is often used in a pejorative sense, to refer to an excessively narrow focus on factual historical trivia, to the exclusion of a sense of historical context or process.
I have heard that in Europe there is more open-mindedness towards numismatics, even some degrees offered in it; but unfortunately in the US, we have quite a ways to go.