I am not so sure wings on spaceships can be passed off as being for atmospheric travel. For a wing to generate any lift at all it's got to be a particular shape. Otherwise it's at best useless, and at worst could cause extra drag and make atmospheric flight less efficent and harder to control. The ships all seem to get around in the atmosphere using their thrusters to generate lift and directional control just fine, so the wings are likely just for ornament or for other reasons like the heat disipation already mentioned.
There's also the Treknobable explanations about needing certain shapes and placements of interior components to generate the right shape of warp bubble or something.
Geoschmo
I'm not an Aeronautical Engineer, but I play one in the forum. 