My biggest issue with this kind of thing is that some species travels hundreds of thousands of light-years, which would be enormously taxing in time and resources, just to fly around scaring superstitious farmers and to push over some corn? Seems unlikely.
Then again, the longer one lives, the quicker time seems to flow. When I was a kid a 5 minute time-out was forever, and 10 years seemed like an eternity. Now, the past 8 years seemed to fly by, and the last 6 months seemed to have gone by without my notice. Perhaps this perception of time dilation multiplies with age, so some super long lived species of ETs might not mind spending 10,000 slowly manipulating a population of sentient beings to some unfathomable end.
Possible, but still unlikely. But, to keep with the skeptical atmosphere, nearly 40,000 generations of evolution and there were no discernible speciation events in human ancestral history, but the past several thousand years (only a few thousand generations) we went from using stone tools to space flight. Aliens, God, or just pure evolutionary chance?