Those surreys are mainly intended for rental at tourist places. You take the family, ride down the bike trail a bit, laugh, have fun, get tired, and take it back. I remember one place I looked at, they rented bicycles by the day and surreys by the hour. Meaning, they're really not intended to be the functional equivalent of bicycles.
One of the surreys I looked at, used an internally geared hub on each wheel. They also had an option using a single internally geared hub, but I'm not sure how that was chained up. They might have just had one wheel driving in that case, too.
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"be careful this rando stuff is addictive and dan's the 'pusher'."