I met a pipeline patrol guy. He landed to warm up in a tiny airport in Iowa in the middle of winter. He was cold, very cold, after a flight, despite wearing heavy Carhart overalls. He remarked that the heat in his 182 wasn't all that it was cracked up to be.
I asked him what he did, and he said that he flew low, and mostly he looked for signs of farmers digging where they shouldn't. Typically the farmers were digging trenches to install tiling for drainage control.
It sounds like a perfect job for a drone. I'd guess this is a profession that won't last.
When he was done with his route in Iowa, he returned to Michigan by flying south of Chicago -- he would not fly over Lake Michigan in his 182.