Two things:
One, the FDA thing is absolutely right. Marijuana was made illegal BEFORE cocaine. Cocaine was one of the last long-standing drugs to be made illicit, and that was because it had such an effective lobbying body (in government, people) to keep it around for a long time. It was alcohol and aspirin (analgesics) companies that got cocaine banned, and tobacco that got rid of marijuana. Heroin was banned once people realized it was HIGHLY addictive. Things can be addictive in society, it's when you start costing the wrong people money (either the government or special interests) that it becomes a problem. If bunches of people were dying from herion use at no expense to the state, it would be harder to get it banned than if they were racking up expensive hospital bills and THEN dying. Today that has changed, and there is a lot more of a humanitarian lean in government, people really do seem to care about the welfare of the citizenry more. However, things that cost the state -- or the people that donate to PAC's and candidates -- money move far more quickly through drafting, legislature, and implementation than "cost-neutral" events. I work for the Governor of Indiana, and am exposed to this stuff almost daily. But before everyone starts ranting about the government, let me tell you from personal experience (and as a former cynic) that there are a lot of good people working in government. Now THAT was off topic.
#2: back on topic:
The coke myths are just myths for regular coke. However, coke concentrate does indeed carry a hazardous materials warning during transport. Phosphoric acid is found in all sorts of things, like orange juice, breath mints, candies, and most of the sodas out there. We ingest citric acids every time we have oj. "Acid" does not mean something bad. But even the phrase "concentrate" is misleading. The "concentrate" that comes in bags and is given to restaurants is not the same as some concentrates that are made at the plant. Those concentrates are not, to my knowledge, transported very often. Coke concentrate without the sugar has a VERY acidic pH.
And the mild acid will, like other acids, aid in cleaning/degreasing/stain removing. It's the same concept as using citric acid cleaners, which we all know are suprisingly effective.