I suppose someone should tell the criminals.
> there's a limit (which I can change) to how much can be transferred per day.
I expect many banks/cards have this ability as well. People just don't use it.
Hell, I have a virtual card I frequently use on websites that has a $50 limit per day. I'm sure most other companies have something similar available.
Outside of the US, the banks do tell the criminals - otherwise the banks would be the hook. This is the fundamental difference between the US and the RoW: in the US, fraudulent withdrawals are the depositors problem[1] which banks don't expend too much effort into, elsewhere, it's the banks' problem, consequently banks go the extra mile to prevent fraudulent withdrawals, and when it does happen, are quick to make the depositor whole.
1. This and "identity theft" are emblematic of a mostly American tendency to pass the buck (and losses) to the least powerful and least informed entity (the depositor) for fraud committed against financial institutions using depositor's information.
I think they already know, because their efforts are mostly focused on trying to get that authorization. But whether you know about it or not, no authorization means you can't access the money. Requiring explicit authorization is key to security, and I'm extremely wary of payment systems that don't require it, like credit cards.
How does the German banking system prevent an unscrupulous online retailer from charging you 500€ for a 50€ item? Or charging you twice?
There are related payment schemes though that do initiate a push payment (i.e. SEPA credit transfer), giving the accountholder control over the amount and payee, but they are not yet as ubiquitous or usable internationally.
The payment page spins until I click ok on it in the phone, since my bank wont accept the transaction otherwise.
What you are referring to is called 3DS, and it's a feature of both credit and debit cards. (It's available worldwide, but most commonly used in the EU, since it's mandated for ecommerce card transactions in many circumstances.)
I do think it's possible to authorize an unspecified amount; automated gas pumps seem to do that, but they seem to be the only ones, and it probably has a hard maximum.
Of course any PIN transaction that goes through the merchant's equipment is not quite as secure and relies on a level of trust that's not necessary for online payments, where I give my authorization through my own bank's website.
shop [> mollie] > iDEAL > ABN > shop
or
(pc) shop QR > (phone) photo app > iDEAL > ABN