How on earth do the forests survive with all of the wild animals ignoring our advice?
Simple question of animals per square mile versus people per square mile.
A little bit of poo out in the wild is just excellent fertilizer that doesn't botter anyone. But you don't want a lot of poo and toilet paper in areas that see a lot of visits.
It seems a lot of people have trouble putting their "if I do this it can't really botter anyone" - habbits into perspective. And that is not only related to where and how to defecate properly...
I think you sum it up pretty well. But also it is easy for people forget that we are relatively large areas. Assuming we only ate plants, and baring agriculture, we would need a couple of acres per person. And eating meat only makes it worse. On both ends. We quickly consume native populations, the supply of deer won't last very long if significant numbers of people use them as their main source of meat, and the feces of meat eaters break down much more slowly than ruminants.
Depending on resource density and the rate of breakdown of waste it may take several square miles per person to meet their needs. This also explain why certain areas, like near rivers that attract game and support plant growth, are historically attractive to humans. High resource density and the easy access to water and rapid rate of waste breakdown, or their being washed away, make life a lot easier for humans. The fertility of the 'fertile crescent' arcing through present day Iran and Iraq and the Nile delta were comparatively easy places to live. Which why they became advances early civilizations and also areas have been swept by conflict so many times.
Another consideration is that modern humans aren't exposed to as many parasites and diseases. Giardiasis (Giardia), beaver fever, is a relatively recent issue. But it isn't a new disease. Beavers carry it but seem to be immune. The fact is that most Americans before the age of rigorous sanitation were exposed to giardia as children. A lot of the babies died, either directly from it, mostly from dehydration from diarrhea, or as a result of some secondary infection. It was just a fact of life that babies got sick and some died. With sanitized water supplies, free of giardia, fewer babies died. But it means that whereas almost every adult in the 1800s was immune to giardia, because they had survived exposure as children, very few modern Americans are immune.
Daniel Boone was likely immune to giardia. The streams he drank from had giardia cysts in them. He also likely had limited immunity to a number of other diseases that he had been exposed to. He was also one of the few who survived childhood and made it into adulthood. In same areas the majority of children died before they were six years old. If you made it to eight you could consider yourself lucky. But celebrate quickly because most adults in the age didn't see forty.
There is a considerable amount of evidence that hundreds of years ago, after the susceptible children had died, most people had limited immunity to many diseases. This is often seen in undeveloped countries. It isn't that the natives are entirely immune to dysentery, for example, rather when exposed their symptoms are less dramatic. What would have us doubled up in pain is simply 'an upset stomach' for them the natives might clear the infection over time, or their bodies might have come to an agreement with the disease and become symptom free carriers. The infamous "typhoid Mary" showed no symptom of typhoid but her feces were alive with it. Traveling from house to house working as a cook she left a trail of dead bodies.
The woods are alive with animals that carry diseases. And certain humans carry diseases. Diseases most of us have no immunity to because we have cleaned up our food and water. This has saved millions of lives and meant we live longer and happier lives. But it also means that we are much more vulnerable to pathogens most of our founding fathers were immune to. It means we have to be very careful about sanitation of our food and water and it means we need to be careful with how we, and those around us, dispose of our wastes.
Historically disease has killed far more humans than all the wars combined. Modern sanitation was perhaps the single most important development ever. But it is a blade that cuts both ways. We are safer, happier and more productive people because of it. But we are also more vulnerable if the components of modern sanitation break down.