Missed opportunity for every 50 feet a wheelybin with the Royal Cypher and a uniformed scooper with jaunty hat snd a gilt-handled shovel.
No, they come along after all the horses are gone. That’s why the royal parks have such lovely flowerbeds.
That’d be the problem then. The Rose Parade has them walking along in the procession. Poop is scooped moments after it’s deposited.
I recall a statistic from my youth in L.A. It was meant as a rejoinder to people complaining about smog from all the cars. I can't vouch for its factual accuracy but I can vouch for my recollection.
If all the cars in Los Angeles were replaced by horses, the horseshit on the freeways would be 80 feet deep by the end of the first day.
Thought provoking to say the least. 
(Where’s the horrified poop emoticon when we need one? Happy poop just isn’t the same thing. 
)
I’ve seen the horse riders in an Independence Day parade followed by the city street sweeper trucks. In another parade, the horse riders are followed by a local company that removes dog poop from people’s yards.
Removing “used food” of all sorts of origins from city streets used to be a Very Big Deal until the advent of modern sewage and the automobile.
There’s a couple of reasons equestrian boots are knee-high. Road apples are probably one of them.
Scottish soccer fans voice their support :-
Tiaras! Tiaras!
My dad organized the parade celebrating my home town’s 350th anniversary in the 1990s. When asked by our local paper what kind of thinking went into making a successful parade, his response was, “Leave the horses 'til last.”
I had heard the advice as, “You can have marching bands or horses in a parade, but not both.”
And that’s what for example the Paris Bastille Day Parade does. The horse guards go after all the foot units.
There’s an old joke that the guy employed by the circus to follow the elephants and scoop up their huge and stinky droppings is asked by a friend why he doesn’t just quit. The guy, shocked, replies, “What, and give up show business?”
What kind of wimpy marching bands are those? If you were lucky, the organizers had a pooper scooper after the horses or maybe the Shriners would squish it down with their little cars, but my high school band marched behind mounted units.
Uphill in the snow. 
I did say it was advice, and advice is not always heeded.
It was small town Minnesota, but the earliest parade I remember was Memorial Day, and even up there the snow is usually gone by then.
An odd case. If he ordinarily would be entitled to police protection (and I would think he would be, even as a “non-working royal,” given his place in the line of succession, his past Army service and the threats against both him and his wife), why not, as a matter of discretion, permit him to reimburse HMG for the expenses of such protection? He’s offering, and he can certainly afford it.
“Why not” is because he apparently he is not entitled to police protection as a non-working royal or as the fifth in line for the throne and it seems whatever threats have been made to or about him and his wife wouldn’t qualify an ordinary person for police protection. And it’s not a good look to allow certain wealthy and well-connected individuals to buy police protection for a number of reasons. One of which is that it tends to make others suspect that their interests are subordinate to the “paying customers “.
No reason he can’t pay for his own private security, but you can’t really say “I want to be Royal for some purposes but not for others”
He is at inherent risk because he had the misfortune to be born into that bullshit. A little help isn’t unreasonable.
Police protection on the public dime - or, at any rate, the level of police protection that working royals get - was withdrawn from him in 2020 by some committee which considers such matters. He reckons he needs that level of protection, and offered to pay for it. That offer was declined. The present court challenge is against the decision to decline the offer of payment.