I would imagine getting a return on the cost of the initial purchase and upkeep of the beach would be the reason.

People don't respect public property; you see how they litter and some actually vandalize, so who would want that on a place they pay good money for to enjoy the view.

This is the reason for gated communities and cul-de-sac layouts instead of grids, to limit access. People on the common causeway litter, let their pets do their business and are loud and obnoxious on their phones and blast their music.

Another prime example public transportation versus private transportation. Would you take a public conveyance today if you didn't' have to? Especially in crime ridden cities?

Entitlement isn't an argument for access in my book nor is equity. Even the Soviets had Dachas for the fortunate to escape the press of humanity if only for a bit.

In my opinion, find a way to join a beach club, get a timeshare or purchase a property if you so desire a nice beach getaway versus the public venues.