So many people use parks even without paths that a common technique for park designers is to simply build parks with no pathways then go pave where people go over time -- so called "Desire Paths." https://en.wikipedia.org/wiki/Desire_path

People have been walking through things like Temple Gardens for most if not all of recorded history. https://en.wikipedia.org/wiki/History_of_gardening

While psychedelics have a long history - and surely some wild animals unintentionally microdose including homo sapiens in the early days just by trying a mushroom they see - it seems certain that it's many orders of magnitude more hours of the human experience spent on walks in nature than on psychedelics.