Yeah, I feel that people who dismiss these concerns by saying "well you can always tell the cop no" haven't had many/any adversarial encounters with the police.

I haven't had many, but I had a few when I was in college. When you lawfully refuse a request from the police, they don't just say "ok" and move on. They apply all kinds of pressure. They make veiled threats, they detain you longer, they get angry, they scare you. It is a lot easier to say what you would do while you are safe at home behind your keyboard.