The clauses are common in the UK but I see them all the time from startups incorporated in Delaware. Maybe they're there for the deterrent factor. Also, hi!
Yes, they get put in but if you try to enforce them you'll find that you can't.
We sign contracts with non-poaching elements in them all the time because the companies we look at are afraid that we will use our inside knowledge to go after their best talent. But I suspect that just the basic protections an employee has under employment law would be enough to stop a company from trying to enforce this (we have a term for this in Dutch which is called 'broodroof' but I don't know any good English translation).
That said: for Execs and consultants it is a different matter. But they are not rank-and-file employees.
