Yes, it would be. I don't know the property law in the State of Florida but I would think the developer should be obligated to inform by letter to every property owner of his intention to let the lakefront go to default thus giving them an option to buy. The newspaper ad is a cheesy way out of it!
Agreed that property owners should be aware of such and ask for such provisions in their sale agreements. If doing so means getting the state legislature to pass a law requiring it, then so be it.