It is a unique luxury that humans share with cats, simply doing nothing. It is because we are so smart that all our basic needs are covered, we don't need to butcher a cow today, or actually catch that fish. We just buy food, and eat it. Easy. Plenty of time left to do nothing... but nothing gets boring fast for us clever humans, so we play. Sometimes at the beach. Playing is human, and I believe a necessity for mental health.
playing is good, yes. different kinds of playing are more fun for different people (and cats too). i'm just more of a forest cat. i don't recall seeing a lot of cats on beaches, but i have to admit not having spent a lot of time on or near one. and that's the thing for me, there's not a lot of ways for the kind of playing that i can relate to that i'm aware of being able to do on a beach.