One of the new Galactic Conquest maps (Omega) contains two planets with only a “no fighters allowed” icon (nothing else). Was that by design?
In any event, after taking the planet Cantarus (a no fighter allowed planet), I was a bit surprised when a counter-attack by a Nomads fleet from the “Planet of Endless Rain” included a large number of fighter bombers! Those bombers did not damage my fleet at all – in fact, after the battle, six squadrons of bombers were added to my fleet. The odd bit was after moving my fleet away from Cantarus and back again – I got the expected “some of your ships not allowed” message.
Anyway – getting free bombers, if not a bug, is certainly a nice feature!