As you note, Jack, there are very effective ways to address footing/impact stress on pavement for horses. OTOH, NYC had a huge population, ( by many accounts over a million), dray horses into the 20th century which led to the formation of the NYC PSD to clean up the sh*t ! With every horse dropping 20+lbs of fecal matter/day where do you suppose it ended up when you're surrounded by water ?
Today, if the horse carriages were banned the horses would end up as dog food and NYC would lose another tourist attraction ! >MW
"Horses belong in pastures with other horses, on grass..."
do you know what happens when you put a horse out in a pasture, with everything it needs close to hand(er, hoof)? the same thing that happen when you put a human in a comfortable climate controlled house in front of a computer with everything they could possibly ever want, all the food they want, without having to work, or exercise, or do anything more strenuous then walk to and from the fridge and the bathroom. just picture it in your mind. yeah, that's what happens.