Nice catch, thanks, it needs to be fixed.
It’s just for that validation of the SafeKey URL matching the SK you provide, so it may not be that useful, only if for some reason you want to have the extra check to confirm the SafeKey URL corresponds to the SK, it’s just that. It may make more sense once we have support for hardware wallets, as discussed in another thread, you specify which key to check the balance for but the SK is obtained from the hardware wallet.