I had a buddy in Chicago who did that. He rode his uni on the sidewalks, took it to the bus stop, then carried it aboard the bus. This was 20+ years ago.
I think unicycle speeds are more appropriate to the sidewalk...closer to walking speeds than a bicycle. They also maneuver more like a pedestrian than a vehicle.
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Religion is a good thing for good people and a bad thing for bad people. --H. Richard Niebuhr