There are other places as well, but in generally all of the places where there is concern campgrounds provided bear boxes. In regular campgrounds you can judge the risk pretty well by whether trash cans and dumpsters are bear proof . If not you can probably assume that bears will not be a problem.
So true. I've been to a campground or two and saw some "be aware of bears" signs, then noticed that all the trashcans and dumpsters were not secured. So I didn't worry much, since the campground itself wasn't taking the appropriate precautions. And honestly, a bear is most likely going to go for the trashcans and dumpsters.
But as pdlamb said, "Keep your lawyers away from me!" Use your own discretion and not take my opinion as truth or law.
One thing to also be aware about when it comes to food is raccoons. There are some places that don't offer "bear boxes" but suffer from raccoon problems (the campsites on the Oregon Coast for example.) While raccoons don't pose as much a threat to humans as bears (well, the non-rabid ones), they do pose a huge threat to your food. And will go through great lengths to get to your food.