To the lovely young (white) couple standing in line ahead of me, who recognized and began a lengthy, enthusiastic conversation with the lovely young (white) couple standing in line behind me:
The polite thing to do would've been to offer to let me move ahead of you in line, instead of talking through me like I don't exist.
The totally dismissible Asian person standing directly in the middle of your happy little group
p.s. The whole, shake hands around me thing, that was a bit over the top, even for normal non-acknowledgement of my existence.