I see a solution to both sides being presented; instead of having the police approach the Ocer, why not have the police observe, note there is nothing to investigate, and approach (but not the Ocer) the citizen who called? Surely then the citizen could still be educated to the legality of OC, and be more likely to believe it when they hear it directly from the horse's mouth.
The cops will make contact because if they don't, the caller will call again demanding to know where they are, because they've been watching.
In my work, I often get the cops called on my by people concerned that I'm a burglar or stalker. The cops come by, we chat for a moment, then they go on. A couple of years ago, I got a visit from the same deputy every day for an extended period. It got to the point where his dispatcher would simply say that I was near a particular address, the deputy would come by, roll down the window and say "You'll never guess what phone call we got!" then roll away. For the rest of the day, the dispatcher would tell anyone concerned that a deputy had already checked me out and it was nothing to worry about, but the day after, it would happen again.
When the cops get a MWAG call, where all that's happening is that there is a MWAG, lecturing the caller won't help -- there has to be contact or the problem hasn't been resolved. Once the cops walk away, they're covered, the OCer is covered, and a hoplophobe is even more frustrated than before -- I find this MOST enjoyable, and wish that it would happen more!