I think most people tend to look through them. By providing us with such details, Boyle makes us see them as they are, right down to the torn sandals. Kyra's appearance is important to us, because how she looks, and what she wears, is so integral to who she is. Her self worth is completely tied to outward appearances. While Boyle gave us no visual image of Delaney, I do not think we needed one.
Any upscale mall is full of Delaneys.
His thoughts and actions painted his picture for us. No, it didn't really help me to understand enough about the different types of people involved. I am presented with a story involving two couples, two opposing types of people standing across the wall from each other. TC probably made most of us think a little or a lot more in depth about the issue of immigration.