to go a little further - the FCC was created in 1934, this brought a greater degree of regulation to the airwaves, forceing the 'quack' doctors and their 'cure-alls' off of commercial radio in the US. They went across the border and built huge transmitters, often 500000-1000000 watts, larger than any 'clear channel' station in the US at that time or since that time, and they could thus broadcast thier ads to the US market without interference from the US government. the huge stations lured many performers, Carter Family among them, who weren't selling as many records because of the growth in radio entertainment, to cross the border and do radio there. Woody Guthrie also worked for a Mexican station for a while, good salaries and great airplay. Carter family never really endorsed the products I don't think, but the good music ensured the listening audience for the quacks to pitch their products to. THe Crazy Water was started in Mineral Wells, Texas in the late 19th c., another of the 'spa craze' era towns that 'sprung' up. The product mentioned above became illegal to advertise in US, so they went across the border into Mexico.