I did this a few years ago. With googly eyes, cat ears, and a nose, people generally responded with a smile. But there wasn't a lot of attention. In coffee houses, subways and buses, meetups, etc. Some parks. Ears made from (two colors of) gaff tape. :) Nose was a monocular passthru camera, gaff taped to various headsets. Sometimes also had an MIT VR sticker, to help people with any "what flavor of wacky is this?" uncertainty. It was tethered, without raised-hand gesturing, so "just a person working on laptop". Perhaps supporting personalization might help smooth hmd adoption?