Now that is a much better question, but as I keep saying -- this is not a moral issue. It's courtesy and common sense to leave the natural world alone for others to enjoy, and for it to thrive.
As for shelling on a beach, there is a beach on Kaua'i known as Glass Beach. Not that long ago -- maybe 5-6 years ago -- it had a ton of polished glass, caused by a combination of the location of an old dump and the wave action on the small crescent of sand. Once Glass Beach became known, and more people visited and "collected" the glass, it started to disappear. People would post images of their hauls -- sometimes it would be a mason jar full of glass that would end up on a shelf. Now there is no more glass on Glass Beach -- none! So you tell me, would it be better if the glass was still on the beach, or is it better on the shelf? The same discussion can be had about multiple shells on Kaua'i including the current favorite of collectors, the Sunrise shell.