T'Challa was already there taking up some of the free drinks. It was a hot day, and he wasn't going to say no to anything free. He was no longer a king, and as such he realized he would have to learn to be more conservative with his spending habits. It was a more conscious effort than most people probably had to go through he realized, but any small thing was a good start.

Luke might not have recognized him right away depending on his canon point, but T'Challa is quick to see him. He gives Luke a small smile. "You seem in surprisingly good spirits considering the circumstances. I have not heard you use one unpleasantry or curse." The joke was he had only just seen him maybe a minute ago.