A Police/Sheriff's Dept. Helicopter is usually manned by a Law Enforcement Officer and police spotter that have years of training in what is legal and what is illegal to do when it comes to your personal civil rights in that city/county/state.
Military style drones manned by government entities not of your area will be manned remotely by personnel with no such training and probably who could not give a hoot about your personal civil rights locally or maybe even nationally.
Why is that important?
Bill of Rights - 4th Amendment - The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no warrants shall issue, but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.
So when you start seeing people getting served with search warrants, summonses or indictments because of some "violation" spotted from the air, you know what is up. For years police abused the system of helicopters by flying over neighborhoods and using Forward Looking Infra Red to scan the roofs of homes. If you had a higher heat signature than your neighbors, they assumed you were growing pot in the attic and got search warrants to kick in your door. This finally came to an end when the courts demanded a higher level of proof than a "hot roof" at night, but that is just the fix, and does not make up for all of those persons whose door was kick in and who were handcuffed on the floor while their Lilly Growing home business was ransacked.
Get the idea why I do not want untrained military or civilians flying over and looking at every inch of my property now? Everyone better uproot every Japanese Maple that has what looks like marijuana type leaves, or any possible personal shooting ranges where you might have "lead contamination" in violation of some obscure EPA rule, or worst of all, they find a Diamond Backed Snail Darter Brood Sow on the property, even if it was just passing through, and declare your entire farm a protected wetland wildscape and demand you pack up and abandon the property immediately, cease all farm operations and forfeit it to the government.
Don't believe that could happen? Already has......Google around and find plenty of "wetlands" declared post facto and people forced into court to try to use their own properties.
And yes, I know I invented the Diamond Backed Snail Darter Brood Sow, but watch the government decide they exist and come flying over my place looking for them now ...........