Chances are that Cas will be very forward with the crowd when he abducts her. Eventually other people in town might not even take a second look when they see it. Maybe. Some of them are still in therapy for what other world angels did to them. It was explained to them at least that Angels are not seeking to start apocalypse on this side.

Something eventually might overshadow that they have doppelgangers of themselves running around. The town's gossip factory is still young. "Yeah, well um... Ruby and I didn't exactly want anything big. It's just...us really." He won't say that Lucy poked her nose into it but she kind of did. It's bigger than just them now. Sam kind of gets that he should have told Dean somehow; he doesn't need to see Dean's surprise to gather what Dean thinks or might have thought once upon a time. It surprises him a little that Dean basically accepts the invitation (unspoken or otherwise) by asking for a dress code. He feels compelled to turn his eyes the side where Ruby isn't standing than turn back.

"I mean... a suit or your best would do the trick?" He's sure they're both aware that requires a little digging. Lucy would surely offer Dean something from the town's collection.

After a lengthy pause, "It would be nice to see you...there."