Don't drag anything to the beach. Just get close to the water and start to dig a hole. When the hole is about a foot deep the kid will take over and all you do is encourage them to dig and keep a good conversation going. Before long the kid is worn out, you get some Sun & there's nothing to drag back to the condo. Have a nice cool glass of wine & relax.
Yeah, dump trucks rock the boys. Please teach them the importance of leaving the dunes and beach vegetation alone ;-)
Why do people feel the need for shovels at the beach? This really perplexes me. Last week, my six year old nephew was visiting and we went to the beach each day he was in town. We took absolutely nothing to the beach, not even a towel. We played in the water's edge (red flag day), dug enough sand with our hands to make many sandcastles, had a blast knocking down the sandcastles, filled in the holes by pushing the sand with our feet, walked down the beach, collected a handful of shells. The kid was in heaven, and so was I. Hands are great tools.

hands were used on the beach, were used long before shovels, for making sandcastles and digging holes. Using hands is probably more "classic and time-honored," than using shovels. Seriously, my six year old nephew never even mentioned shovel, and we both dug with our hands. It was fun getting in touch with the earth, much like kneading dough compared with putting it all in an automated mixer.