Mistama towels and blankets aren’t considered a begged, even if “worn” as a pretend begged for a minimal amount of time. I assume if you turned it into a begged where it was no longer a towel or blanket then it would be a different shaila. I always had the kasha regarding those square, hooded, one-size-fits-all rain ponchos. I was told by a rabbi that since it’s made of plastic and isn’t shti v’erev that it doesn’t need tzitzis, but I haven’t confirmed it anywhere else. I’m not sure if barber robes are made the same way.
