FD,
Welcome! (even though I'm basically new myself)
Your jacket, by itself, wouldn't necessarily cause any alarm.
15 years ago, I was the grocery manager for a 24hr store, which meant a lot of overnights. Everyone was taught to see everyone who entered the store. Someone in a light jacket, unzipped, who seemed normal, would not seem unusual.
IF (big IF) all the speculation is true, and he went to the store at 4:20am, bundled up in a jacket with a hat pulled over his face, he would have been noticed. When I was working that shift, the cashier would have made it a point to alert me to his presence, and we would have known where he was at all times, even if we didn't "watch him" 100% of the time. It's probably safe to assume that if all the speculation is true, BC probably wouldn't have seemed normal. He probably would have been quiet and nervous, which would cause more red flags for the store personnel. They would have been glad to see him leave.
The store employees would have noticed him out of self-preservation, and then when he was shown on WRAL they would have probably recognized him in about 3 seconds.