This is not a hack. It's a thing non-tech people have been doing for quite some time. Indeed, you can simply call the hotel and ask them if they have any discounts (including event-related discounts) during the period of your stay, and they'll gladly tell you if it means they get your business.

It's always jarring to read something that techies call a "hack" which is something that non-techies consider common sense. What is localfu going to "discover" next? That you can ask the concierge desk to book reservations at popular restaurants?