I've never been to Caymen, I try and avoid beach destinations that are too 'Americanized'. Plus, I've always heard it was very, very expensive.
So, I was surprised to read that food costs are similar to San Pedro. We live here in the winter and eat out fairly often. At the very high end places, you can certainly spend US30-40.00 for a meal, but, we rarely do.
I can get fresh fish, either whole or filleted, as a dinner for well under US$20.00.
I love fried chicken, I know, not very tropical, but, I get 1/4 fried chicken for US$7.50, including a small salad and a baked potato.
And, that's at a tourist oriented restaurant. At local places, food is cheaper. Grilled chicken dinners for US$6.00. Burritos from the food stands in the park for US$2.00 or so.
Beers are US$2-3.00. Rum drinks about the same. Imported liquor is expensive. Wine is expensive, although I guess it's relative, US$7.50 really isn't that much for a decent glass of wine. I'm just used to beer prices.