This is true. Our neighbor has multiple cameras I don't KNOW that he doesn't have a grow op, but I know he has expensive cars, expensive tractors and farming equipment, and lots of animals. Out in these parts, you pretty much just assume everyone has firearms as well.
We have firearms for protection and practice shooting in the summer - we also have cameras because we have home nursing for my nonverbal immobile 3.5 year old son, not that I don't trust the nurses in my home, because I don't leave them here alone until I do, but it makes me feel better that I can check them, just in case. And he wouldn't be able to tell us if something was happening. We also have a camera outside, but that was installed after we caught a nurse going outside to smoke a cigarette after we had went to bed, which we were clear we did not want happening. So now we have one out there just to see what a nurse does if she exits the house. Is she grabbing something from her car, or is she going out to smoke, or is she even having someone "stop over". We have no grow operations in our house, cameras are just more common these days IMO.
So with that said, IF we did have a grow operation, I could definitely see us equipping with cameras of some sort. Trail cams, wireless cams, small cams, obvious cams, something.