I think it's less the situation of CO not needing these 'concierges,' and more about providing them all the proper training.
Consistency is THE key to repeat business. Under-promise and over-deliver. I've flown BF dozens of times over the past 4 years and only three times have I been greeted or even acknowledged by the grey coat. Granted, I haven't needed their help, but if CO wants to compete with premium airline services like BA and VS, they're going to need to step it up a little.
From what I've seen, most of the concierges are older, a bit slow and are most likely CO employees that have been moved from other parts of ops. Sort of CO's way of putting out their once-best to pasture.
BN