!!!UPDATE 01/21/16!!!
I spent my morning trainer session waving at strangers on Zwift, took some screenshots-
Attachment 499571Attachment 499572Attachment 499573
NOT A SINGLE WAVE IN RESPONSE. I even dinged my bell just to make sure they saw me, and then rode alongside each person and waved at least 12-15 times to see if they'd wave back. A couple of them just accelerated and dropped me, one did a quick u-turn to get away, and another immediately disconnected.
CONCLUSION:
Virtual riders are jerks. They race-faced me and I feel like this game is no longer enjoyable.
Please discuss.