I'm going to assume you are referring to running a debit as a credit.
Only reason I wished I could've done it at Macy's was because it wasn't my card and I didn't know the PIN, but I had permission from the owner to use the card. Macy's forces you to run a debit as a debit, and I agree with this. I see zero reason to run a debit as a credit, except for that situation I was in. But, in reality, it should be blocked. What if that person didn't know I had their card? I could just charge it up all day, whereas if debit is forced to run as debit, and you don't know the PIN, you're SOL.
Correct, those benefits are only for actual credit cards. Running debit as credit affords no extra benefits. The only reason we even have the option to run a debit card as a credit card in America is because the FTC deemed that it needed to happen for "consumer choice" and "competition".
Yeah, running my card thru VISA's tubes instead of PULSE or STAR's tubes, which makes literally zero difference to me, is such a competitive advantage to me...