haha i think people have overharvested it from the wild in an effort to sell based on the purported drug test benefits. i think mainly people read the misinformation online and buy from the many online retailers available.
as for it's uses, i have personally used it to great affect for the above-mentioned mucous relief in later stage of a cold and also as an immune booster and digestive tonic. i can speak to all of those benefits! we've also used it with great success to aid in relieving painful poison ivy rash (used as a topical wash in this instance). I can't speak to any of the other claims, but I have researched this medicine extensively and trust many of the herbal sources i've read. A lot of this information is from Paul Bergner's Healing Power of Echinacea and Goldenseal. Hope this helps!
Oh and I just reread your comment- per reputation and effects are you referring to use as a drug masker in testing-- haha i just gave you another plant profile! It is ineffective in terms of masking drug tests (for a friend ;) lol!)