I kinda understand you but having to confirm every little thing that I want to do would get pretty annoying very fast.
When there's a new update including new outfits, I tend to refresh the shop very often as well as the film offers.
I'm totally into collecting outfits and that's why I can't resist hunting for them using diamonds for shop and film refreshs.
Actually I am refreshing the shop several 100 times then and it would be so annoying if I had to confirm every shop or film refresh.
Another example:
I want to get that special convention outfit. So what do I do? I'm skipping many convention missions very often.
Having to confirm this everytime would be such a pain.
So I definitely don't want to be forced to confirm every little thing I want to do.
Missclicking is no fun at all, but the only thing you have to do is to be more careful.
On the other side, every player that uses diamonds regularly would be totally annoyed by such a mandatory confirmation.
And this is probably the reason why Playata would never implement such a confirmation button.
The only acceptable way to implement a confirmation function would be if it was optional, for example via the game options.
But a mandatory confirmation for every little thing that costs diamonds would definitly be more annoying then helpful.