I am older and it seems to me that the Start up companies that hire only the best, do so to build their system then they replace them with cheaper people, if the company makes it.

Plus why would you want to work for a startup? That is the most unstable stage of a company. A large portion of startups fail. I've done it several times. So you are better off consulting a startup than working for one.

Startups will give you a great marketing speach and try to promise if you work for cheap or free that you get xxx amount of company stock and you too will get rich = STARTUP

If you are the best at what you do start a consulting company. That is what I am doing right now.