I work for a mobile design and development agency. We get many inquiries from clients with zero budget and a "million dollar idea" that is doomed from the start

I work for a mobile design and development agency. We get many inquiries from clients with zero budget and a "million dollar idea" that is doomed from the start. When they hear the cost, that's usually the last we hear from them. Looking at the app, I really can't believe they spent this much creating it. My immediate reaction is it's a bad outsourcing job with clipart purchased from Fiverr. Also, the screenshots and App/Play Store presence is just awful.