Considering the movie was probably shot along the California coast you have to agree it is a plausible hypothesis. Plus the monsters are always accompanied by strange clacking sounds which I suppose is their limbs and joints. Personally it reminds me of an evening at Red Lobster, listening to a fat guy two tables over attack his dinner with cracker and mallet. You sir, are a truly disgusting human being. With the island reduced to a small rock outcropping and the last crab monster closing in all seems lost, until Hank climbs the antenna and brings it down on the advancing horror in a shower of sparks.
Few things get more mileage than stock footage of cold war nuclear tests.
God is available for voice-overs. The wild ocean looks just like an overstocked aquarium. Newly formed sinkholes should not have shrubs growing out of their sides. When demolition experts play poker they use sticks of dynamite instead of money or chips. Crabs are mimics and ventriloquists.