Honestly, I don't know how I can stop it without an everstone. I was using an EXP Share and well it just evolved, I couldn't even stop it.
Get out, if you aren't no help then just leave. You see that X on the corner, yeah click it. thx bye
Right now pokeyen is obtained in the following way:
Grinding.
And I will tell you right now, grinding is NO fun whatsoever. And so, I suggest that there should be other methods of earning poke yen.
Examples
Daily logins
Every x hours you earn y money
Make the Elite 4 give money
Maybe pokeballs that are randomly spawned in the world that has some money in them?
If there is more ways to earn pokeyen then it would solve the issue about shiny rates.