Partnering with local cafes to promote my news app, yay or nay?

Thinking of an idea to market my news app:

1. I buy some digital credits/vouchers from a local cafe and put them as Easter eggs in my news app.
2. After a lucky user reads N number of news threads (my news app reads like a tweet), we show the Easter egg, and they have to complete a trivia question related to the news they just read. If they get it right, they win a voucher.
3. In return to my voucher purchase, I'd ask the cafe to put up my flyers to promote my app.

Good or stupid idea?