Just an observation as a retired LEO in a large metro area. We have, by last count 4+ million residents in the county. I am not sure of the number of city jurisdictions but the largest city is 1.5 million and probably 40 or more city and county jurisdictions make up the rest. You can literally cross a street and be in a different city or county. So, the purpose of this is that going to the local police station is a pretty worthless contact and calling a dispatch center won't get the information to the other 40 or so dispatch centers. If you live in an area where you can go to one location and check, that is great but most in major metro areas cannot and I will tell you that most police officers are way to busy with real crime problems to worry about a person flying a drone, unless of course you are flying in an area you should not be and someone calls. Bottom line, know your state and local laws. That is your responsibility and if an LEO stops by while you are flying, don't argue. Stop what you are doing. If you know you are within your legal rights contact the watch commander and explain that. He/She will make the proper corrections or explain why the officer was out to see you.
I read too many threads where someone was flying, was contacted by the local police and "gave him/her a piece of their mind". Flunking the attitude test right off the bat is not going to help your cause. In most cases the officer is there because he/she was sent there and is doing the job they are paid to do. Try civility. It works wonders with these contacts.