Well, yes and no. If you have a crew, and the crew isn't your family, then someone is liable in case of an injury or damage to property. And there are laws regarding parking, stopped traffic and the like. You need liability coverage if your brother isn't shooting. Otherwise, you could lose your house, or your car, or your rig, or all of the above...
If you film on *private* property and get a release form signed from the owner, and you're not violating local noise laws, you should be fine regarding permits in most places. Still, the private property owner is liable for any damage and injuries there and if he's smart he'll make you get insurance to cover any damage/injuries during your shoot.
Once you move onto public property, though, you really should get the permit or you risk getting busted by one of the nation's finest. If you get the permit, then they can give you police coverage, block off streets and whatnot, but you have to have typically $1,000,000 in business liability coverage to do it. This kind of liability coverage is pretty standard in the business world and protects you against getting sued when stupid happens (and it will - remember Michael Jackson's Pepsi videothe one where his hair caught on fire?. That kind of set stupidity is why you or the video producer needs insurance.)
So, really, the goverment is making sure *they* don't get stuck with a legal bill if you are careless on the set on their property. That's why you need the permit. It's really due diligence on their part. There are also issues with damaging sensitive wildlife areas if you decide to get back to nature when you shoot.
Other than that, I think goverments like having videos shot as it improves the local economy and generates buzz they can hoot about.