The answer to the question above is; “Both.” As technology increases our individual capabilities, there is an ever-smaller distinction between these two worlds.
In fact, I would go so far as to say that everything you do short of asking for a contract is marketing. Until you ask for a signature on the dotted line, you are painting pictures, telling stories, and creating a vision. All of which are central to the field of marketing.
Of course, the marketing you do on behalf of each individual client or prospect is a highly refined version of what the more general marketing staff is up to. They have to try to figure out what the market wants and needs in the aggregate. As a salesperson, you have the advantage of being able to craft a situation- and client-specific story that will speak directly to known individuals
All of which means that we could do their job. I wonder if they could do ours?