I would argue that keeping wild animals reflects a need to contact nature and therefore contributes to a basic human need. It is not the only way but it is one way to have a contact with nature in todays industrialized nations. Where there is not an explicit reason to prevent it I think it should be encouraged or at least allowed. If it's going cost more to enact and enforce unecessary regulations than it would to enact and enforce reasonable ones that's good reason to spend a little money on research.
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