Labs, like any dogs, learn most of their behaviour. Because many people expect them to be dustbins, many people treat them like dustbins and don't admonish bad habits, using their breed as an excuse. Train it, starting now, and it will know it's boundaries. Our lab could be left in a room with a plate of dinner on the floor and we knew the food would be safe. Nothing was given to him from human plates, his food was always put in his bowl, especially the scraps and everything was wonderful.
The other thing is to consider a crate. Our dogs love their crates, sleep in them during the day and the current mutt is trained to go straight into his crate when the doorbell goes. Being able to invite visitors into the house without them getting mugged by an excited dog is very useful, especially if you have kids who invite friends round. He considers the crate to be his home, his den, and has never stressed when in there, so we can now leave him in there for a couple of hours without worrying about what he might have eaten when we get back. We have another crate in the back of the car, which is again fantastic as you can open the boot safely without any chance of him jumping out, and it means that we can put other stuff in the back of the car with him, knowing it won't crowd him or fall on him. He'd probably also be better protected in an accident.
A crate costs about as much as Jake shredded.