Okay, here's something I see quite often, and it's unfortunate because it makes me literally convulse with nausea every time.
A human being walks out their front door, and begins blowing their nose onto the sidewalk. Without a tissue. Just blowing the contents of their nostrils onto the sidewalk.
There is no way I can think of to sufficiently describe how horrifying this is to me. I'd rather rabid elephants with tentacles and antennae take over the world, enslave humanity, and force us all to watch Dr. Phil for hours a day than see people blow streams of snot all over the sidewalks of the city.
What is going on inside your house that makes you have to come outside and do this in front of me? Is it a dust bowl in there?
After 8 hours a day working in an environment where people try not to spread infectuous diseases, I walk outside to see people painting the sidewalks with their mucous.
When did this become something people do? Ever since I was a kid I've taken tissues with me when I left the house. I think most people did. I don't ever remember waiting for the school bus, and seeing another kid emptying his nose all over the street. When did it become acceptable, even common to do such a thing? Did some popular artist write a song about it? Is it an environmental thing? Because if it is, hankies work too. They're washable, dryable and re-usable.
There are literally hundreds of other options out there besides just spraying it all over the ground. Think about it. You manage to hold in your poop! You don't just squat on the sidewalk and crap all over it whenever the urge arises, do you? If you can manage that, there's no reason you can't wait until you find a tissue or a handkerchief.