Flightless anthropomorphic avian species are an oddity. With arms instead of wings, birds lose their greatest advantage.
Perhaps in the case of these Therian birds, they recall their ancestors abilities of flight with great affection, and lament that for generations western settlers have outlawed flight. The wings and by extension their very way of life had been phased out, as young birds are forced to keep their feathers trimmed.

And from there simmers obvious cultural tension and resentment. Well, that on top of the whole 'ethnic cleansing' thing, of course.