If you want a $23 plate of gluten-free spaghetti vongole at Ballerina—the restaurant at Miami’s Oceana Bal Harbour—you must first spend several million dollars on a condominium. Tables in the sun-washed Piero Lissoni-designed establishment are exclusively for residents of the tower, where units range from $3.9 million to $19.85 million.

“The food is so good—I’m vegan, no gluten, and always the people are very nice,” said Patricia della Giovampaola d’Arenberg, a philanthropist and former model who bought a two-bedroom condominium...