I agree that no free seat selection for Concierge is a major shortcoming in the scheme.
I've recently become concierge having moved a chunk of TA travel from BA after the "Club" changes and that fact I was no longer going to maintain GGL yet already had Gold for Life.
I genuinely thought it was a system glitch when I tried to book seats and was asked to pay as I don't know of any other FF top tier that pays for seat selection?