Listening to your gut when it comes to a firearm transaction is not profiling. Dude had gangbanger written all over his face. Well, sorta all over.
Profiling is not illegal. Everyone does it every single day. You may not want to admit but you do it. It's part of the collective experiences of life. If those three guys walked up to my table I'd politely refuse their cash. I was in OAS a few years back when a wannabe gangbanger came in and asked if he could buy just 10 9mm rounds. They shoulda refused the sell. Instead they sold him a whole box. Left there just SMDH.