Hate that. Yes, some issue can be resolver faster by talking in person, but that can be accomplished by a phone call, too. Just like a face to face conversation can end in an hour of gossip. How's that for more efficient?
Back when a lot of my work conversations were with sales reps and system engineers over the phone, certain reps in particular would take 10 minutes to get to a point where they could have been handled in a minute with an internal email. Though, yes, sometimes the real-time conversation was useful.
Sales is hard. For some it comes naturally, others have had to work at it. A good sales person is valuable, and a good relationship with a sales person is very valuable, especially to those of us of the engineering breed.
Give them the time, build the relationships, could be worth the effort.
On a busy day, I resented it sometimes. And there were a few who, when I got a call from them, I silently sighed. But, as a product manager, keeping field people happy was part of my job and I mostly did.