This is a good point. IANAL, but I imagine there definitely are routes to take when drafting various legal documents (e.g. employment contracts) that would all

This is a good point. IANAL, but I imagine there definitely are routes to take when drafting various legal documents (e.g. employment contracts) that would allow employees to pursue personal projects. Its likely just easier (and as you say in the company's best interest) to avoid figuring out how to word such clauses.