well, i think thats only because of our history.chettri,magars and gurungs were the core of gorkhali army. and everyone knows the reputation  of gorkhalis.

and by the way newars are the most privilaged non-durbariyas(shahs n ranas).and they are ALSO  full of communial bias against non-newars(marsya and khwasa names were given by newars).so pointing at B-C is not the solution.

timi pahila newar bhitrakai discrimination(shakyas,shresthas,kasai ,jyapu and so on) hatau .thats more serious.i ve seen bahuns marrying rai or kami marrying chhetris but i ve also seen a kasai  guy being beaten to death by the girls side(guvaju).

sabai jaat ma jatiya pride hunchha.but being proud on ur cast/creed doesnt mean u must humiliate the other. (eg-a patriot paki mustnt be an anti-indian and the other way round)