Backstory: I've recently traveled to Denver quite a bit for work. Denver is an awesome city with unique and different cultural influences. Often times when I ask for restaurant or bar recommendation, people preface it with if you like "hipster, country, modern, etc" then you'd like this place.
The Idea: A demographic based ranking system for bars and restaurants.
Deep Dive: Similar to yelp and hoodmaps, users would be able to tag restaurants and bars with categories like hipster, modern, country, loud, private, etc. These categories would help differentiate the type of atmosphere the end users are looking for.
You could also tap into yelp and other services for reviews. The key differentiating factor is being able to view a map of only "hipster" type bars.
Validation: People tend to associate with a type of culture and this is a way for those to find others in their same sphere.
Monetization: At scale you would be able to charge restaurants to be featured on a daily basis. You could also run promotions for restaurant week, where restaurants and bars would pay to be featured.