Something (else) odd about a lot of humans believing that something heavier is better, even pets. I've heard more than one person (almost always a guy) say, "I've got a 150 pound Rottweiler (or any other large breed) and he's great." No sir, you have an overweight dog.
Someone could build an amp out of magnesium and people would probably think it isn't that good because of how light it would be except magnesium has one of the highest strength to weight ratios. As my dad would say, use your head for something other than a hat rack.