Wrong. They're designed to boost an already healthy diet, not to replace good eating. Most people, even if they eat clean and well for the most part, could use a little extra support. Our environments are toxic, we also take in things like alcohol and prescription drugs that deplete minerals and stress our systems, we're under constant stress, and working out, though healthy, adds to that load. Supps on top of healthy diet and sleep can be good. But they are no replacement.
Bare minimum: Clean diet, loads of veggies, sleep, fish oil and vitamin E, B-complex, Greens supplement, multimineral (a good one without loads of binders and fillers).
Vitamin C could also be considered a bare minimum supp by some. Others, like older women, might consider Cal-mag-vitamin D to be an essential. Bare essentials will to some extent depend on the individual.