Total gamechanger when we got one. They DO mean you can take more crap, but that means everyone has more fun. The difference between 'we can take what we can collectively carry' and loading up a trolley is a day at the beach where the adults can relax and the children can move between building sandcastles, playing cricket, playing football, playing frisbee, flying a kite, bodyboarding (with an adult), reading, napping in the shade of a parasol... It's the difference between a picnic lunch, and a feast with snacks. Plenty of drinks, no need to spend loads trekking to a cafe. Wetsuits, sea shoes and blankets on colder days.
I'm such an advocate. A full day of free activities you already own on wheels, rather than kids whinging after 2 hours that they're bored or cold or wet. Nothing gets lost or left behind either. It's a beach cupboard. We used to keep all the toys and games in a couple of bags for life ready to sling in, all the wetsuits, snorkels and beach shoes in another, a third with blankets and picnic blankets. Chuck the beach chairs, parasol, picnic and drinks and body boards on top and you're good to go. Lifesaver as a single mum/solo parent for the day.
Nothing to do with lazy kids or lazy parenting. Some things are an improvement on the way we did things in the past.