Monterey bike path

Why one oughtn't have headphones/earphones on while running or walking on the bike path:

1. The barking of the seals and sea lions is missed
2. AND the sound of the otters crunching abalone 
3. AND the sound of birds chirping 
4. AND the sound of waves crashing or kayakers paddling 
5. you are unaware of your surroundings 
6. you don't get to say good morning/good day/good afternoon/good evening to your fellow runners/walkers/bikers

Good morning, Monterey, view from my commute to work

the Wharf