Amen. I never quite understood what benefit (pardon the pun) it served, although I've got some idea of the origins of employer-provided health insurance.
The cynical part of me believes it's definitely a way for larger companies to hold more control over their employees, and they may lobby for this because it provides an extra advantage over smaller competitors.
I've known plenty of really sharp/talented folks whose talents may better serve the economy by taking those skills to other companies (sometimes in other parts of the country). "But I'll lose my health insurance" is almost always a primary reason why people've stayed in their job (however crappy it might be otherwise re: pay, commute, colleagues, boss, industry, etc). This seems like it's been a real drag on labor mobility for some time now.
I would have thought 'conservatives' would be all over a 'free market' where people make their own choices with their own money. They'll happily deride a "nanny-state" as fostering people who just want the govt to provide them with everything, but ... expecting people to need employers to provide access to basic services? Apparently there's no problem there whatsoever, and it doesn't even seem contradictory to many I talk to.