Ajahn Brahmavamso is British (Aussie citizen now I think?) and talks matter of factly about experiencing ghosts, including helping to persuade one to move out of the house it had occupied as a human in Perth, Australia.
For me, if there are no ghosts, devas etc, it would also bring in to question other dhammic teachings, much as I find the Christian Bible unbelievable as soon as they mention there being a firmamament between the earth and the sky (That's just me, I'm not attacking Christianity). If there are no decvas, how was it taht Anathapindika visited the Buddhas as a Deva after being rebornn as one? If there were no devas, how is it that there are Suttas that are supposed records of talks given to Devas? That's a lot of 'metaphor' there and to introduce patent lies in to the Sutta mix would seem to be bizarrely unbuddhist, the compiler of such a 'Sutta' would be violating the precept against false speech wouldn't they?