I just came across something called "Eat Offers" I'm assuming this is a brand new thing as it's not showing up in any google searches.

The one I found is for a restaurant called Casa Avila in Terminal B of SJU and they're basically offering a choice of one of three dishes. PP gives you a QR code voucher that I guess entitles you to that dish for free. No mention of additional guests for more dishes, no mention of gratuity or anything else.

I'll be able to report first hand on this in about a week, but any details sooner would be welcome!