I can't see why. If implemented in very crowded areas where using umbrellas is completely stupid. They are unnecessary - just go and buy a decent raincoat ffs. I was in causeway bay during some (light) rain last week and I was astounded at the number of people getting out their umbrellas for basically drizzle, keeping them up under covered walkways, walking into me and everyone else on very narrow streets - it's just stupid and unnecessary. I don't think HK would be laughed at; I think it would be applauded!