You realize the mobile gaming market is mostly micro transactions and it has nothing to do with Google? The same happened to the PC gaming over the last ten years. You can blame customers for their human nature of feeling good for beating their in-game enemies with money to compensate for their psychological deficiencies.
Yes, not ideal, but better than mere website.
Even better option would be a dedicated password manager with MFA like Proton Pass etc. but banks use their authentications in various ways and are regulated more.