I can't afford as many lawyers as Google can. Do you have examples of cases where a Google-style IP agreement was ruled unenforceable when someone was moonlighting on something that was in the same field of business as some other part of the company (but unrelated to their own day job)?
From another hand there are thousands of ex-googlers left company to engage in startups, and Google likely doesn't have enough lawyers to go after each of them..
You're not arguing that it's legal; you're arguing that you're unlikely to get caught. That's different.
Left to join/found a startup is different from working simultaneously at both.
Yes, but Google need some resources to monitor and research who exactly left to found, and who was working simultaneously at both with conflict of company interests.