Gamora gets up, still holding the towel just for the sake of having something in her hands, and walks over to look over his shoulder at a slight distance. When Sam opens the case and says it's 'creepy', that must mean he recognizes some of the things inside.

"Maybe they wanted you to be comfortable here." Or something like that. Really, there's no way of knowing what their captors are thinking. The steak is an oddity among a book and some clothes. "Given what little food I've seen here, you might want to preserve that before it goes bad."