To the OP, what years are your other Gibsons?
IME, every new Gibson USA guitar I've bought has the vanilla smell (I switched to Gibsons in 2001) and it is not due to the case (though cases have their own smell).
The Gibsons that shipped new with gigbags had the vanilla smell, as do guitars off the shelf at stores, many of which have been on display for several months.
There's gotta be something different in the Gibson formula or how thy buff them out or something, as the nitro finishes I've done on guitars, or Fender nitro finishes lack the particular scent on the Gibsons (although they do have a nitro smell of their own)