From a medical standpoint, it is not the nicotine that causes the cancer, it is all of the other chemicals within the tobacco that does that. Nicotine is a drug - an addictive drug - and is used regularly in the medical field in safe and therapeutic ways. Tobacco on the other hand, is a drug BECAUSE of the nicotine, but is not used in medical treatment because it is also responsible for causing cancer.
Take the nic out of tobacco and it is no longer a drug, yet it will still cause cancer and kill you. And if they tell you they take all the cancer causing elements out of tobacco, they are either liars or it isn't tobacco.
Fake dip can be helpful in dealing with the physical need of a pinch that, to some (I find myself among these), is a large part of the addiction - the oral fixation. People use seeds, fake dip, candy, mints and all sorts of other things to help get over the need to have something in their mouth. In my opinion, as long as it isn't something that is going to kill you and doesn't have nic, it should be looked at as a positive thing. But remember, over use of candy can result in diabetes, overeating can lead to obesity and heart disease and diabetes. Moderation is a good thing.