Missclicking is a thing, regardless of platform, and the confirmation screen when pulling with raw primos does help you stop and think about what you're soing.

I used to convert primos immediately to wishes, until one time I was distracted talking to a friend while going through menus and did a 10 pull on a banner while trying to click on my History instead. Since then I have actually missclicked again on the exact same situation, distracted by a conversation - but since I don't convert primos anymore because of that first incident, the "are you sure" screen made me stop and read and backpedal before I wasted wishes again.

The other reason people don't convert is because they refresh resin with primos. This is not something f2p/low spenders ever think about doing, but high spenders will want their primos/crystals freed up for the ocasional refresh.