It's not purely population though. My neighbourhood has a desire path, where the grass has been killed off my people walking through it. The traffic is a few people an hour, mostly kids.

However, one of the main parks has similar areas where you get 10s to 100s of people an hour, or people covering it up for extended periods of time for picnics, etc. If population was all that mattered, the park would be barren and the path would be lush, rather than the other way around