ah, cool. thanks for clearing that up, what I meant of course too.
Not sure if that is what the OP meant. I'd never run across ads for those "good brands", but then I don't subscribe to more than a couple of magazines any more, no newspapers, and I'm not exactly in a metro market where I might see that carried by a local retailer either. those are the good ones, "real copper" as I mentioned. Have seen far far too many ads for the "Copper Chef" or whatever TV-brand stuff and many places selling it. Just like the "Green pan" stuff before it, and so on and so on going back to the Ginsu (that's the first big TV brand kitchen thing I remember).
Not to totally discount the point made above about most commercial settings using cheap but efficient Aluminum & much of the home market being Stainless or Cast Iron, which I would say is a likely true observation, I have seen exceptions to this 'rule'. If he's intrigued by the real copper, maybe he should check out a simple piece? (Or if he's suggesting you try it, maybe you should?) ... my personal take on it is this --
yeah, in commercial settings they are common. and I even have a couple of pieces myself. I can sometimes "taste" (or even worse, "see") the Aluminum pans' use like that, so when I cook, I always have something that won't do that like the anodized sort (calphalon commercial was my go-to for years), or stainless. cast iron? yeah. love it. for some things. and I think the enameled stuff also has a place (really like those dutch ovens for stove-top/oven use). same deal with my (not all All-)Clad pans, gain some of the efficient heating from the copper or aluminum in the sandwich and still have an easy/non-reactive surface. same with the copper... I think they are really fun to cook with, very responsive to small changes of the knob and uniform across the cooking surface. but they take some extra care. but really, good pans do, not just copper ones. you have to tend to your black steel and cast iron too. even the cheap durable aluminum ones can discolor and get pitted if you abuse them.
hopefully we've helped you with your question, OP.