Because years ago, William Randolph Hurst and Harry J. Anslinger ran a smear campaign on hemp, as it was a high risk of running their cotton mill and production lines out of business. It's only been over the past few years that it has been given serious reconsideration as to its medicinal health benefits. Most states are leaning towards or already in the process of medical legalization. Other states, like Colorado, have legalized it for recreational use, because it provides medical and relaxing effects, and is more healthy of an activity than consuming alcohol.