During my cargo haulin days, some of the more remote fields we'd go into we would make low passes down the runways to scare off any wildlife lurking about. had a Captain who would go so low at one airport he returned to base one evening having clipped a fence post at the end of runway.
Kids with weed eaters on the runway
An old woman with Alzheimer's (sp?)
The kid with the weed eater was at a public airport and he was wearing faded jeans and a grey t-shirt (as close to runway camo as you can get). His sunglasses saved his life. 1st day on the job, he had no radio, no high-vis colors, nothing. I guess nobody told him to watch his azz while on the runway. Very last-second go around. The old lady was in her 80s, private airport. I was in a 520 commander landing on a 2000' strip when she wandered right out in to the runway for some reason. Had to go around.
I fly out of private strips a lot in my free time and the subject comes up from time to time about low passes. My point, and I will stick to it no matter who is asking, is that I like to make it clear that I am in the area and about to land. Going down for a look and to make some noise is a good idea, IMO. Gives people a chance to round up their animals and grandmas, and put the maintenance equipment down for a second. I don't expect to pull objects out of the ground, but I am an advocate of a good low pass at private and quiet public airports; I think of it as a legitimate safety issue. Total bonus that I also enjoy it.