Car Dealer 'Admin' fees' ?

[bigdog]

I've been looking at car dealers on-line for a good used car.
I've seen a few dealers, including Grappone in Concord, that are charging
an 'Admin Fee'. Not singing out Grappone, as I notice others are doing also.

On the car I was interested there was a &550 Admin applied.
WTH is the Admin fee ? Is this just an 'up charge' the dealers are charging
because the can ! Is this a common charge among dealers ?

Thanks for you responses !