One of the things that I had to learn with our dogs (2 big labs) is that not all exercise is created equal. We have a backyard and we leave the door open so they can run in and out all day, but that just wasn't doing it for them - they still had those bad behaviors often associated with too much energy/boredom. Taking them on walks away from the home is not only physically tiring, but mentally stimulating. I can tell when we have not taken them for a walk - bad behaviors everywhere! Walking together also allows you to set up the hierarchy of your home - our dogs know we're the boss (simply from how our walks go) so when they are misbehaving in the home, it only takes a simple correction to get them to stop.
Like you, our dogs seemed to like all the other things that normally help this behavior (spray bottles, putting tobasco on our fingers to stop them from mouthing our hands....they loved all of it!)