I see a lot of green fruit pigeons here in Thailand too.. in the jungle and nature reserves.
I don't think they make good aviary or coop birds, because their diet is mostly mushy wet fruit.. and they poop huge amounts of watery slimy smelly stuff all over the place.. shooting it up the walls too!! (I used to take care of some when I worked as a zoo keeper back in the UK).
They are very beautiful through.
Why don't you put some green food colouring in white coloured pigeons bathing water and you will have some nice green 'normal' pigeons. I had a friend who coloured his white homes like that.. all the colours of the rainbow... they looked amazing flying about.