Is there some kind of scam where scammers ask for your private locked photos without even attempting an introduction? I get a lot of requests for my private photos on SA. Most of the requests seem to be from brand new accounts that have very little in the way of a profile. I don't grant access to them, I attempt to engage them in some kind of convo but most of the time they don't answer. I was thinking that maybe scammers use the photos to set up fake SD accounts although I don't see much point in that since to do so would cost a membership fee.

Most likely they’re scammers. If they do engage in convo I’d bet more often than not they will ask for money for something.  Videos, pictures, or a deposit.  I have one that’s in my rotation who became real. The rest have all been time bandits.

Yes, but why do they ask to unlock my photos? They could try to scam without that extra step.

Potential to use your photos against you. Expose you to your family. I’ve had someone try that, threaten to expose me, it never materialized. But that’s my guess as to why.