You must have worked in some shitty companies. HR is treated differently in different companies. The ones you worked in sound like companies where the HR department has some incestuous relationship with the C-suite (or more likely, the owner). That's not the norm for all companies; in better-run companies, HR only functions at the pleasure of the departments that actually make money. So if a hiring manager wants to hire someone, that person gets hired (assuming the department head supports the decision), and any problems from HR result in the department head (for instance, engineering) going to the CEO and telling them to do something about HR.

I've seen horror stories about companies like yours on places like glassdoor.com. Those are places to be avoided at all costs.