Moving Shacks on Cape Cod

Back in the late 80s when I was in MA and went to do my first survey in the Truro area, I had to recover some benchmarks set (I believe) by USC&GS in the dunes.  Many of the ties to the benchmarks were corners of buildings.  We kept tying in locations and digging...nothing no matter how deep; things just didn't seem to fit. Fortunately it was soft sand.  Finally talked with master at lighthouse and found out that every year after seasonal storms, people would simply pickup the "buildings" and move them around.  No foundations.  Never did find any benchmarks.  This article reminded me of those times.

https://news.yahoo.com/fight-over-dune-shacks-cape-174758510.html?guccounter=1