At the very begining there were 3 types of commanders: the ones that you could get by progression, ones that were given to people who pre-ordered and the ones that went only to people who got the extended/deluxe/whatever more expensive edition.
The commanders from last group couldn't even be bought by others for quite a long time after release. If I remember correctly they were released for sale about the time first iteration of war spoils came out. So it was something elite for the time. The only problem being that these commanders are generally trash ones.
It would have been unfair if these were better than vanilla ones though.
