I was under the impression that there were legitimate, erosion-based reasons for doing this. Basically, by building a gradual, sloped shore it causes waves to b

I was under the impression that there were legitimate, erosion-based reasons for doing this. Basically, by building a gradual, sloped shore it causes waves to break smaller and over a longer distance, reducing shoreline erosion. Sure they dump the sand in front of the nice houses first because people want it there, but they would still dredge the beaches even if they were abandoned. Or that's the theory at least. But I only remember reading it somewhere, not where I read it; so I don't know if it's BS pseudoscience. Does anyone who actually knows something about the science behind shoreline erosion have an opinion?