I dont know if involve money in type of game like this is a good idea..
It will become a huge trade market instead of a GAME.
I think that collecting bitcoin by playing games it's an awesome idea. I think when app developer create this type of games, They will for sure succeed.
When we talk about POKEMON GO, It's very a nice games which allow us to collect our pokemons by walking and walking and catch them, If developper add this option in it, it will be more awesome i think.