Never have I had anyone say something like, "I've always wanted a 24-35mm zoom lens for my Canon DSLR, and I think it would be a good seller -- so I'm going to start a company to makes lenses like that." No one has ever told me they wanted to start a company to create anything they may have a fantasy about.
And I'm willing to bet $2 right now that the OP would not produce such a lens (even a contracted one-off) if he were handed $100 million on a Monday morning.
Talk is cheap. And nothing personal, but sometimes it's also silly.
Maybe most people don’t, but some do.
I don’t play, but I was given anything North of 100000€, I would put a part (like 5-10%) aside for me, and use the remainder to create new products I’ve been dreaming about for a long time.
I think it may depend on the background: I’ve always wanted to create products and dream of things that could be useful, at least for me. That’s what draw me to engineering.