The answer here is pretty simple, they are called spitting tobacco because once you get done getting all of the flavor and nicotine out of it you then would spit it out, in some bars they actually have something called a "spittoon" that is literally a can that is used for spitting the tobacco in, chewing tobacco is really bad for you health because using it can result in tooth decay and gum disease plus there are 28 different types of cancer causing chemicals in chewing tobacco which can result in gum cancer and esophagus cancer. It can also cause cardiovascular disease which can result in heart attacks.
In all actuality chewing tobacco is just as bad as smoking it