HUGE difference. If I choose not to buy anything Toyota, I have other options, or I can ride a bicycle, walk, etc. I don't have such direct choices in the areas of law. That, and a government LEO is required to adhere to the law and not infringe on my rights. If s/he does, s/he has the potential of having charges placed against him/her.
My rights and liberties are paramount. I'm not going to simply roll over and do what a LEO would like just because s/he would like it. To do so is to voluntarily give up those rights we still have.
Laugh if you want, present your papers if you so choose. I'd rather hold the duty each one of us has to stand up to those in power and retain our liberties.
Actually there are approximately 195 countries in the world so you can leave the US any time you want to just like you don't have to buy Toyota.