Then they should protect that with non-disclosure agreements, or realise that they can't survive as a business (or don't want to) without restricting the freedo

Then they should protect that with non-disclosure agreements, or realise that they can't survive as a business (or don't want to) without restricting the freedom of the workers to do what they want to outside of the time paid to the employee in the form of wage. I have little or no sympathy for businesses which insist on restricting freedom outside of those hours for which it pays me wage.