Exactly. In fact, Dining.Gifts does exactly that - it displays all restaurants whose information is published on the Hive blockchain on a map.
Yes, you can filter restaurants by the type of food they serve and the amenities they offer. You can even search the map to find out which nearby restaurant serves a particular dish.
All of the data, including user reviews and sponsored rewards offered by restaurants in exchange for sharing two or more photos of their dishes, is publicly available on the Hive blockchain.