I grew up in Miami. I can't imagine living more than a few hours drive from the ocean. So I sort of understand. FWIW, Hawaiians, Puerto Ricans, and other island-living Americans probably get it too. :-)
I grew up very near the Puget Sound in Washington state, and I feel the same way!
I just did a bit of research and discovered that in 2010, 39% of Americans lived in a coastal county. Given that many counties are rather small, especially on the East Coast, I wouldn't be surprised if as many as 50 or 60% of Americans lived within 70 miles of the coast.