A couple of points:
Vintage aircraft (however you define that) owners rarely fly very far. I know a fair few and they stick very much to the local area, most never venturing past a 50-100nm radius. After doing this for 30 years, you get to know the place pretty well! I would not expect the typical WW1 aircraft owner to EVER feature in CAS busts.
I WOULD expect the "younger" owners of slow planes to feature however. Speaking to one Class A ATCO recently, they do very much feature (microlights, etc).
PPLs are usually told to not talk to ATC at busy Class D airports. My PPL instructor (who claimed to hold a CAA ATPL; probably a fake like so much in aviation) told me "don't ever talk to Gatwick - they will shoot you down and destroy your confidence so much you will never want to fly again". I know it's easy (usually) to get a VFR transit through the Gatwick zone, 2400ft, but equally I rarely bother because it's easy to go round it. There is some truth in this negative approach however because one is much more likely to get a transit if calling up confidently and presenting a clear route, A-B-C-D, not "would like a transit please, south to north" especially if without a transponder.