Even in 1967 (I was a teenager and regular watcher of the Ed Sullivan Show), I knew "magic" wasn't real and that those who performed it used scientific principles to dupe their audiences. As for The Lovin' Spoonful, when acts like that came on I took the opportunity to use the bathroom and/or get some munchies from the kitchen. My preferences even then were for performances of bossa nova and jazz rather than the then-popular "music." Time spent on the high school bus, where rock blared continuously, triggered my allergy to it. It also motivated my abandoning the bus for the last two years and walking back and forth to school -- two miles away -- despite winter weather.
Of course they do. Why would they advertise to their audiences that what they're doing is illusion based on science? P.T. Barnum's dictum is why they earn a living; truthfulness would kill the golden goose.