I wonder if financial marketing understands this? Associating credit with less risk, less requirements, in naming of the networks themselves? Even though settlement can occur on each network
But turns out it's pretty difficult to hide the complexity, and many businesses are built around hiding it as a service. It usually involves taking on risks others aren't willing to or having an Apple-like resolve to piss off some customers by deciding what's best for them without asking or, rarely, the power and/or innovation to actually change how things are done.
It sounds like your bank has made the decision to eat the small liability as a customer value add.
One of the reasons why people are often wrong about CC being safer than debit is because many banks will also make you whole the next day after reporting fraud rather than waiting for it to process before returning the funds. They're not legally required to do this, but neither are credit card companies, both are doing it to gain customers.
Exactly how long the transaction takes to _clear_ your account may vary depending on the semantics of the network and integration used, but processing a debit card over a credit network doesn't mean you get to hold onto your money for any longer than you would otherwise. The auth will put a hold on the funds in your account instantly and you will effectively have that much less money in your account.